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  • How do I solve this "unexpected '}' syntax error" in my bash script?

    - by WASasquatch
    I have a piece of code that has some serious issues and I was hoping to get it solved soon but no one has offered any help. I thought I'd try some Ubuntu users since this is the OS running the script. mc_addplugin() { if pgrep -u $USERNAME -f $SERVICE > /dev/null then echo "$SERVICE is running! Please stop the service before adding a plugin." else echo "Paste the URL to the .JAR Plugin..." read JARURL JARNAME=$(basename "$JARURL") if [ -d "$TEMPPLUGINS" ] then as_user "cd $PLUGINSPATH && wget -r -A.jar $JARURL -o temp_plugins/$JARNAME" else as_user "cd $PLUGINSPATH && mkdir $TEMPPLUGINS && wget -r -A.jar $JARURL -o temp_plugins/$JARNAME" fi if [ -f "$TMPDIR/$JARNAME" ] then if [ -f "$PLUGINSPATH/$JARNAME" ] then if `diff $PLUGINSPATH/$JARNAME $TMPDIR/$JARNAME >/dev/null` then echo "You are already running the latest version of $JARNAME." else NOW=`date "+%Y-%m-%d_%Hh%M"` echo "Are you sure you want to overwrite this plugin? [Y/n]" echo "Note: Your old plugin will be moved to the "$TEMPPLUGINS" folder with todays date." select yn in "Yes" "No"; do case $yn in Yes ) as_user "mv $PLUGINSPATH/$JARNAME $TEMPPLUGINS/${JARNAME}_${NOW} && mv $TEMPPLUGINS/$JARNAME $PLUGINSPATH/$JARNAME"; break;; No ) echo "The plugin has not been installed! Removing temporary plugin and exiting..." as_user "rm $TEMPPLUGINS/$JARNAME"; exit;; esac done echo "Would you like to start the $SERVICE now? [Y/n]" select yn in "Yes" "No"; do case $yn in Yes ) mc_start; break;; No ) "$SERVICE not running! To start the service run: /etc/init.d/craftbukkit start"; exit;; esac done fi else echo "Are you sure you want to add this new plugin? [Y/n]" select yn in "Yes" "No"; do case $yn in Yes ) as_user "mv $PLUGINSPATH/$JARNAME $TEMPPLUGINS/${JARNAME}_${NOW} && mv $TEMPPLUGINS/$JARNAME $PLUGINSPATH/$JARNAME"; break;; No ) echo "The plugin has not been installed! Removing temporary plugin and exiting..." as_user "rm $TEMPPLUGINS/$JARNAME"; exit;; esac done echo "Would you like to start the $SERVICE now? [Y/n]?" select yn in "Yes" "No"; do case $yn in Yes ) mc_start; break;; No ) "$SERVICE not running! To start the service run: /etc/init.d/craftbukkit start"; exit;; esac done fi else echo "Failed to download the plugin from the URL you specified!" exit; fi } It throws it at the closing bracket at the end of the function.

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  • C++ Formatting like visual studio c# formatting

    - by Fire-Dragon-DoL
    I like the way Visual studio (2008) format C# code; unfortunately it seems it doesn't behave in the same way when writing C++ code. For example, when I write a code in this way: class Test { public: int x; Test() {this->x=20;} ~Test(){} }; in C# (ok this is C++ but you can understand what I mean), this part: Test() {this->x=20;} Will become Test() { this->x=20; } This is obviusly a stupid example, but there are a lot of things where putting brackets in correct position, indenting code and other things with my own hands becomes boring. I can obviusly change editor if you suggest me a good one for C++ code, I would like to find something with these features: Intellisense (like vs, at least similiar) Custom class coloring (in c# they are cyan, why are they black in c++?) Wordwrap (possibly) Documentation when you mouse over a method/variable Auto formatting (when you close a bracket like "}" in c# you'll get everything well formatted) obviusly I can find other features, but this is what is in my mind at the moment. Thanks for any suggestion

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  • Preg Expression to identify classes/ids in a CSS file that have no contents

    - by dclowd9901
    I'm in the process of updating some old CSS files in our systems, and we have a bunch that have lots of empty classes simply taking up space in the file. I'd love to learn how to write Regular expressions, but I just don't get them. I'm hoping the more I expose myself to them (with a little more cohesive explanation), the more I'll end up understanding them. The Problem That said, I'm looking for an expression that will identify text followed by a '{' (some have spaces in between, and some do not) and if there are no letters or numbers between that bracket and '}' (spaces don't count), it will be identified as a matching string. I suppose I can trim the whitespace out of the doc before I run a regular expression through it, but I don't want to change the basic structure of the text. I'm hoping to return it into a large <textarea>. Bonus points for explaining the characters and their meanings, and also an expression identifying lines in the copy without any text or numbers, as well. I will likely use the final expression in PHP script. tl;dr: Regular Expression to match: .a_class_or #an_id { /* if there aren't any alphanumerics in here, this should be a matching line of text */ }

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  • How to change identifier quote character in SSIS for connection to ODBC DSN

    - by William Rose
    I'm trying to create an SSIS 2008 Data Source View that reads from an Ingres database via the ODBC driver for Ingres. I've downloaded the Ingres 10 Community Edition to get the ODBC driver, installed it, set up the data access server and a DSN on the server running SSIS. If I connect to the SQL Server 2008 Database Engine on the server running SSIS, I can retrieve data from Ingres over the ODBC DSN by running the following command: SELECT * FROM OPENROWSET( 'MSDASQL' , 'DSN=IngresODBC;UID=testuser;PWD=testpass' , 'SELECT * FROM iitables') So I am quite sure that the ODBC setup is correct. If I try the same query with SQL Server style bracketed identifier quotes, I get an error, as Ingres doesn't support this syntax. SELECT * FROM OPENROWSET( 'MSDASQL' , 'DSN=IngresODBC;UID=testuser;PWD=testpass' , 'SELECT * FROM [iitables]') The error is "[Ingres][Ingres 10.0 ODBC Driver][Ingres 10.0]line 1, Unexpected character '['.". What I am finding is that I get the same error when I try to add tables from Ingres to an SSIS Data Source View. The initial step of selecting the ODBC Provider works fine, and I am shown a list of tables / views to add. I then select any table, and try to add it to the view, and get "ERROR [5000A] [Ingres][Ingres 10.0 ODBC Driver][Ingres 10.0]line 3, Unexpected character '['.". Following Ed Harper's suggestion of creating a named query also seems to be stymied. If I put into my named query the following text: SELECT * FROM "iitables" I still get an error: "ERROR [5000A] [Ingres][Ingres 10.0 ODBC Driver][Ingres 10.0]line 2, Unexpected character '['". According to the error, the query text passed by SSIS to ODBC was: SELECT [iitables].* FROM ( SELECT * FROM "iitables" ) AS [iitables] It seems that SSIS assumes that bracket quote characters are acceptable, when they aren't. How can I persuade it not to use them? Double quotes are acceptable.

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  • how to insert multiple rows using cakephp

    - by Paul
    In the cakePHP project I'm building, I want to insert a defined number of identical records. These will serve as placeholders records that will have additional data added later. Each record will insert the IDs taken from two belongs_to relationships as well as two other string values. What I want to do is be able to enter a value for the number of records I want created, which would equate to how many times the data is looped during save. What I don't know is: 1) how to setup a loop to handle a set number of inserts 2) how to define a form field in cakePHP that only sets the number of records to create. What I've tried is the following: function massAdd() { $inserts_required = 1; while ($inserts_required <= 10) { $this->Match->create(); $this->Match->save($this->data); echo $inserts_required++; } $brackets = $this->Match->Bracket->find('list'); $this->set(compact('brackets')); } What happens is: 1) at the top of the screen, above the doc type, the string 12345678910 is displayed, this is displayed on screen 2) a total of 11 records are created, and only the last record has the values passed in the form. I don't know why 11 records as opposed to 10 are created, and why only the last records has the entered form data? As always, your help and direction is appreciated. -Paul

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  • Readability and IF-block brackets: best practice

    - by MasterPeter
    I am preparing a short tutorial for level 1 uni students learning JavaScript basics. The task is to validate a phone number. The number must not contain non-digits and must be 14 digits long or less. The following code excerpt is what I came up with and I would like to make it as readable as possible. if ( //set of rules for invalid phone number phoneNumber.length == 0 //empty || phoneNumber.length > 14 //too long || /\D/.test(phoneNumber) //contains non-digits ) { setMessageText(invalid); } else { setMessageText(valid); } A simple question I can not quite answer myself and would like to hear your opinions on: How to position the surrounding (outermost) brackets? It's hard to see the difference between a normal and a curly bracket. Do you usually put the last ) on the same line as the last condition? Do you keep the first opening ( on a line by itself? Do you wrap each individual sub-condition in brackets too? Do you align horizontally the first ( with the last ), or do you place the last ) in the same column as the if? Do you keep ) { on a separate line or you place the last ) on the same line with the last sub-condition and then place the opening { on a new line? Or do you just put the ) { on the same line as the last sub-condition? Community wiki. EDIT Please only post opinions regarding the usage and placement of brackets. The code needs not be re-factored. This is for people who have only been introduced to JavaScript a couple of weeks ago. I am not asking for opinions how to write the code so it's shorter or performs better. I would only like to know how do you place brackets around IF-conditions.

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  • What Scheme Does Ghuloum Use?

    - by Don Wakefield
    I'm trying to work my way through Compilers: Backend to Frontend (and Back to Front Again) by Abdulaziz Ghuloum. It seems abbreviated from what one would expect in a full course/seminar, so I'm trying to fill in the pieces myself. For instance, I have tried to use his testing framework in the R5RS flavor of DrScheme, but it doesn't seem to like the macro stuff: src/ghuloum/tests/tests-driver.scm:6:4: read: illegal use of open square bracket I've read his intro paper on the course, An Incremental Approach to Compiler Construction, which gives a great overview of the techniques used, and mentions a couple of Schemes with features one might want to implement for 'extra credit', but he doesn't mention the Scheme he uses in the course. Update I'm still digging into the original question (investigating options such as Petit Scheme suggested by Eli below), but found an interesting link relating to Gholoum's work, so I am including it here. [Ikarus Scheme](http://en.wikipedia.org/wiki/Ikarus_(Scheme_implementation)) is the actual implementation of Ghuloum's ideas, and appears to have been part of his Ph.D. work. It's supposed to be one of the first implementations of R6RS. I'm trying to install Ikarus now, but the configure script doesn't want to recognize my system's install of libgmp.so, so my problems are still unresolved. Example The following example seems to work in PLT 2.4.2 running in DrEd using the Pretty Big (require lang/plt-pretty-big) (load "/Users/donaldwakefield/ghuloum/tests/tests-driver.scm") (load "/Users/donaldwakefield/ghuloum/tests/tests-1.1-req.scm") (define (emit-program x) (unless (integer? x) (error "---")) (emit " .text") (emit " .globl scheme_entry") (emit " .type scheme_entry, @function") (emit "scheme_entry:") (emit " movl $~s, %eax" x) (emit " ret") ) Attempting to replace the require directive with #lang scheme results in the error message foo.scm:7:3: expand: unbound identifier in module in: emit which appears to be due to a failure to load tests-driver.scm. Attempting to use #lang r6rs disables the REPL, which I'd really like to use, so I'm going to try to continue with Pretty Big. My thanks to Eli Barzilay for his patient help.

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  • In asp.Net, writing code in the control tag generates compile error

    - by Nour Sabouny
    Hi this is really strange !! But look at the following asp code: <div runat="server" id="MainDiv"> <%foreach (string str in new string[]{"First#", "Second#"}) { %> <div id="<%=str.Replace("#","div") %>"> </div> <%} %> </div> now if you put this code inside any web page (and don't worry about the moral of this code, I made it just to show the idea) you'll get this error : Compiler Error Message: CS1518: Expected class, delegate, enum, interface, or struct Of course the error has nothing to do with the real problem, I searched for the code that was generated by asp.net and figured out the following : private void @__RenderMainDiv(System.Web.UI.HtmlTextWriter @__w, System.Web.UI.Control parameterContainer) { @__w.Write("\r\n "); #line 20 "blabla\blabla\Default.aspx" foreach (string str in new string[] { "First#", "Second#" }) { #line default #line hidden @__w.Write("\r\n <div id=\""); #line 22 "blabla\blabla\Default.aspx" @__w.Write(str.Replace("#", "div")); #line default #line hidden @__w.Write("\">\r\n "); } This is the code that was generated from the asp page and this is the method that is meant to render our div (MainDiv), I found out that there is a missing bracket "}" that closes the method or the (for loop). now the problem has three parts: 1- first you should have a server control (in our situation is the MainDiv) and I'm not sure if it is only the div tag. 2- HTML control inside the server control and a code inside it using the double quotation mark ( for example <div id="<%=str instead of <div id='<%=str. 3-Any keyword which has block brackets e.g.:for{},while{},using{}...etc. now removing any part, will solve the problem !!! how is this happening ?? any ideas ? BTW: please help me to make the question more obvious, because I couldn't find the best words to describe the problem.

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  • accessing parsed JSON on the iPhone SDK

    - by itai alter
    Hello All! I've been following the great tutorial about (iPhone, json and Flickr API and I did manage to access the parsed json info just fine. Now I'm trying to do the same thing with the Twitter API, and I am able to get the json info and parse it, but I can't seem to access it like in Flickr. I noticed that the json info that is retrieved from Twitter is a little different from Flickr. The Flickr json info starts straight with a curly braces ({), while the Twitter json info starts with a square bracket and then a curly braces ([{). I understand that it means it's an array inside the json info, but I don't know how to access it. In the Flickr example, I access the objects like so (the second line takes the number of pages Flickr has reported): NSDictionary *results = [jsonString JSONValue]; pagesString = [[results objectForKey:@"photos"] objectForKey:@"pages"]; but I can't seem to access the Twitter response in the same way... Does anyone know of a solution? (here's an example of the Twitter JSON response: api.twitter.com/1/statuses/public_timeline.json ) Thanks a bunch!

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  • Jmeter is not extracting correctly the value with the reg ex extractor.

    - by Chris
    Jmeter is not extracting correctly the value with the reg ex. When I play with this reg ex (NAME="token" \s value="([^"]+?)") in reg ex coach with the following html everything work fine but when adding the reg with a reg ex extrator to the request he doesn't found the value even if it's the same html in output. <HTML>< script type="text/javascript" > function dostuff(no, applicationID) { submitAction('APPS_NAME' , 'noSelected=' + no + '&applicationID=' + applicationID); }< /script> <FORM NAME="baseForm" ACTION="" METHOD="POST"> <input type="hidden" NAME="token" value="fc95985af8aa5143a7b1d4fda6759a74" > <div id="loader" align="center"> <div> <strong style="color: #003366;">Loading...</strong> </div> <img src="images/initial-loader.gif" align="top"/> </div> <BODY ONLOAD="dostuff('69489','test');"> From the reg ex extractor reference name: token Regex: (NAME="token" \s value="([^"]+?)") template : $2$ match no.:1 Default value: wrong-token The request following my the POST of the previous code is returning : POST data: token=wrong-token in the next request in the tree viewer. But when I check a the real request in a proxy the token is there. Note : I tried the reg ex without the bracket and doesn't worked either. Do anybody have a idea whats wrong here ? Why jmeter can't find my token with the reg ex extrator ?

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  • C# StackOverflowException

    - by KSwift87
    Problem: I am trying to update a List. If a certain item's ID already exists in the List, I want to add onto that item's quantity. If not, then I want to add another item to the list. cart = (List<OrderItem>)Session["cart"]; for(int counter = cart.Count-1; counter >= 0; counter--) { if (cart[counter].productId == item.productId) { cart[counter].productQuantity += item.productQuantity; } else if (counter == 0) { cart.Add(item); } } "cart[counter]" and "item" represent an instance(s) of a custom object of mine. Currently when I finally find a matching ID, everything APPEARS as though it should work, but I get a StackOverflowException thrown in my custom object class. public int productQuantity { get { return _productQuantity; } set { productQuantity = value; } } It gets thrown right at the open-bracket of the "set". Could somebody please tell me what the heck is wrong because I've been going at this for the past 2+ hours to no avail. Thank you in advance.

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  • Targeted Simplify in Mathematica

    - by Timo
    I generate very long and complex analytic expressions of the general form: (...something not so complex...)(...ditto...)(...ditto...)...lots... When I try to use Simplify, Mathematica grinds to a halt, I am assuming due to the fact that it tries to expand the brackets and or simplify across different brackets. The brackets, while containing long expressions, are easily simplified by Mathematica on their own. Is there some way I can limit the scope of Simplify to a single bracket at a time? Edit: Some additional info and progress. So using the advice from you guys I have now started using something in the vein of In[1]:= trouble = Log[(x + I y) (x - I y) + Sqrt[(a + I b) (a - I b)]]; In[2]:= Replace[trouble, form_ /; (Head[form] == Times) :> Simplify[form],{3}] Out[2]= Log[Sqrt[a^2 + b^2] + (x - I y) (x + I y)] Changing Times to an appropriate head like Plus or Power makes it possible to target the simplification quite accurately. The problem / question that remains, though, is the following: Simplify will still descend deeper than the level specified to Replace, e.g. In[3]:= Replace[trouble, form_ /; (Head[form] == Plus) :> Simplify[form], {1}] Out[3]= Log[Sqrt[a^2 + b^2] + x^2 + y^2] simplifies the square root as well. My plan was to iteratively use Replace from the bottom up one level at a time, but this clearly will result in vast amount of repeated work by Simplify and ultimately result in the exact same bogging down of Mathematica I experienced in the outset. Is there a way to restrict Simplify to a certain level(s)? I realize that this sort of restriction may not produce optimal results, but the idea here is getting something that is "good enough".

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  • IF-block brackets: best practice

    - by MasterPeter
    I am preparing a short tutorial for level 1 uni students learning JavaScript basics. The task is to validate a phone number. The number must not contain non-digits and must be 14 digits long or less. The following code excerpt is what I came up with and I would like to make it as readable as possible. if ( //set of rules for invalid phone number phoneNumber.length == 0 //empty || phoneNumber.length > 14 //too long || /\D/.test(phoneNumber) //contains non-digits ) { setMessageText(invalid); } else { setMessageText(valid); } A simple question I can not quite answer myself and would like to hear your opinions on: How to position the surrounding (outermost) brackets? It's hard to see the difference between a normal and a curly bracket. Do you usually put the last ) on the same line as the last condition? Do you keep the first opening ( on a line by itself? Do you wrap each individual sub-condition in brackets too? Do you align horizontally the first ( with the last ), or do you place the last ) in the same column as the if? Do you keep ) { on a separate line or you place the last ) on the same line with the last sub-condition and then place the opening { on a new line? Or do you just put the ) { on the same line as the last sub-condition? Community wiki.

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  • What is the nicest way to parse this in C++ ?

    - by ereOn
    Hi, In my program, I have a list of "server address" in the following format: host[:port] The brackets here, indicate that the port is optional. host can be a hostname, an IPv4 or IPv6 address. port, if present can be a numeric port number or a service string (like: "http" or "ssh"). If port is present and host is an IPv6 address, host must be in "bracket-enclosed" notation (Example: [::1]) Here are some valid examples: localhost localhost:11211 127.0.0.1:http [::1]:11211 ::1 [::1] And an invalid example: ::1:80 // Invalid: Is this the IPv6 address ::1:80 and a default port, or the IPv6 address ::1 and the port 80 ? ::1:http // This is not ambigous, but for simplicity sake, let's consider this is forbidden as well. My goal is to separate such entries in two parts (obviously host and port). I don't care if either the host or port are invalid as long as they don't contain a : (290.234.34.34.5 is ok for host, it will be rejected in the next process); I just want to separate the two parts, or if there is no port part, to know it somehow. I tried to do something with std::stringstream but everything I come up to seems hacky and not really elegant. How would you do this in C++ ? I don't mind answers in C but C++ is prefered. Any boost solution is welcome as well. Thank you.

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  • Replacing characters in a non well-formed XML body

    - by ryanprayogo
    In a (Java) code that I'm working on, I sometimes deal with a non well-formed XML (represented as a Java String), such as: <root> <foo> bar & baz < quux </foo> </root> Since this XML will eventually need to be unmarshalled (using JAXB), obviously this XML as is will throw exception upon unmarshalling. What's the best way to replace the & and the < to its character entities? For &, it's as easy as: xml.replaceAll("&", "&amp;") However, for the < symbol, it's a bit tricky since obviously I don't want to replace the < that's used for the XML tag opening 'bracket'. Other than scanning the string and manually replacing < in the XML body with &lt;, what other option can you suggest?

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  • MySQL subquery and bracketing

    - by text
    Here are my tables respondents: field sample value respondentid : 1 age : 2 gender : male survey_questions: id : 1 question : Q1 answer : sample answer answers: respondentid : 1 question : Q1 answer : 1 --id of survey question I want to display all respondents who answered the certain survey, display all answers and total all the answer and group them according to the age bracket. I tried using this query: SELECT res.Age, res.Gender, answer.id, answer.respondentid, SUM(CASE WHEN res.Gender='Male' THEN 1 else 0 END) AS males, SUM(CASE WHEN res.Gender='Female' THEN 1 else 0 END) AS females, CASE WHEN res.Age < 1 THEN 'age1' WHEN res.Age BETWEEN 1 AND 4 THEN 'age2' WHEN res.Age BETWEEN 4 AND 9 THEN 'age3' WHEN res.Age BETWEEN 10 AND 14 THEN 'age4' WHEN res.Age BETWEEN 15 AND 19 THEN 'age5' WHEN res.Age BETWEEN 20 AND 29 THEN 'age6' WHEN res.Age BETWEEN 30 AND 39 THEN 'age7' WHEN res.Age BETWEEN 40 AND 49 THEN 'age8' ELSE 'age9' END AS ageband FROM Respondents AS res INNER JOIN Answers as answer ON answer.respondentid=res.respondentid INNER JOIN Questions as question ON answer.Answer=question.id WHERE answer.Question='Q1' GROUP BY ageband ORDER BY res.Age ASC I was able to get the data but the listing of all answers are not present. Do I have to subquery SELECT into my current SELECT statement to show the answers? I want to produce something like this: ex: # of Respondents is 3 ages: 2,3 and 6 Question: what are your favorite subjects? Ages 1-4: subject 1: 1 subject 2: 2 subject 3: 2 total respondents for ages 1-4 : 2 Ages 5-10: subject 1: 1 subject 2: 1 subject 3: 0 total respondents for ages 5-10 : 1

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  • How grouping and totaling are done into three tables using JOIN

    - by text
    Here are my tables respondents: field sample value respondentid : 1 age : 2 gender : male survey_questions: id : 1 question : Q1 answer : sample answer answers: respondentid : 1 question : Q1 answer : 1 --id of survey question I want to display all respondents who answered the certain survey, display all answers and total all the answer and group them according to the age bracket. I tried using this query: $sql = "SELECT res.Age, res.Gender, answer.id, answer.respondentid, SUM(CASE WHEN res.Gender='Male' THEN 1 else 0 END) AS males, SUM(CASE WHEN res.Gender='Female' THEN 1 else 0 END) AS females, CASE WHEN res.Age < 1 THEN 'age1' WHEN res.Age BETWEEN 1 AND 4 THEN 'age2' WHEN res.Age BETWEEN 4 AND 9 THEN 'age3' WHEN res.Age BETWEEN 10 AND 14 THEN 'age4' WHEN res.Age BETWEEN 15 AND 19 THEN 'age5' WHEN res.Age BETWEEN 20 AND 29 THEN 'age6' WHEN res.Age BETWEEN 30 AND 39 THEN 'age7' WHEN res.Age BETWEEN 40 AND 49 THEN 'age8' ELSE 'age9' END AS ageband FROM Respondents AS res INNER JOIN Answers as answer ON answer.respondentid=res.respondentid INNER JOIN Questions as question ON answer.Answer=question.id WHERE answer.Question='Q1' GROUP BY ageband ORDER BY res.Age ASC"; I was able to get the data but the listing of all answers are not present. What's wrong with my query. I want to produce something like this: ex: # of Respondents is 3 ages: 2,3 and 6 Question: what are your favorite subjects? Ages 1-4: subject 1: 1 subject 2: 2 subject 3: 2 total respondents for ages 1-4 : 2 Ages 5-10: subject 1: 1 subject 2: 1 subject 3: 0 total respondents for ages 5-10 : 1

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  • HTML5 and Visual Studio 2010

    - by Harish Ranganathan
    All of us work with Visual Studio (or the free Visual Web Developer Express Edition) for developing web applications targeting ASP.NET / ASP.NET MVC or Silverlight etc.,  Over the years, Visual Studio has grown to a great extent.  From being a simple limited functionality tool in VS.NET 2002 to the multi-faceted, MEF driven Visual Studio 2010, it has come a long way.  And as much as Visual Studio supports rapid web development by generating HTML mark up, it also added intellisense for some of the HTML specifications that one has otherwise monotonously type every time.  Ex.- In Visual Studio 2010, one can just type the angular bracket “<” and then the first keyword “h” or “x” for html or xhtml respectively and then press tab twice and it would render the entire markup required for XHTML or HTML 1.0/1.1 strict/transitional and the fully qualified W3C URL. The same holds good for specifying HTML type declaration.  Now, the difference between HTML and XHTML has been discussed in detail already, though, if you are interested to know, you can read it from http://www.w3schools.com/xhtml/xhtml_html.asp But, the industry trend or the buzz around is HTML5.  With browsers like IE9 Beta, Google Chrome, Firefox 4 etc., supporting HTML5 standards big time, everyone wants to start developing HTML5 based websites. VS developers (like me) often get the question around when would VS start supporting HTML5.  VS 2010 was released last year and HTML5 is still specifications under development.  Clearly, with the timelines we started developing Visual Studio (way back in 2008), HTML5 specs were almost non-existent.  Even today, the HTML5 body recommends not to fully depend on the entire mark up set as they are still under development specs and might change in the future. However, with Visual Studio 2010 SP1 beta, there is quite a bit of support for HTML5 based web development.  In fact, one of my colleagues pointed out that SP1 beta’s major enhancement is its ability to support HTML5 tags and even add server mode to them. Lets look at the existing validation schema available in Visual Studio (Tools – Options – Validation) This is before installing Visual Studio 2010 SP1 Beta.  Clearly, the validation options are restricted to HTML 4.01 and XHTML 1.1 transitional and below. Also, lets consider using some of the new HTML5 input type elements.  (I found out this, just today from my friend, also an, ASP.NET team member) <input type=”email”> is one of the new input type elements according to the HTML5 specification.  Now, this works well if you type it as is  in Visual Studio and the page renders without any issue (since the default behaviour is, if there is an “undefined” type specified to input tag, it would fall back on the default mode, which is text. The moment you add <input type=”email” runat=”server” >, you get an error Naturally you don’t get intellisense support as well for these new tags.  Once you install Visual Studio 2010 Service Pack 1 Beta from here (it takes a while so you need to be patient for the installation to complete), you will start getting additional Validation templates for HTML5, as below:- Once you set this, you can start using HTML5 elements in your web page without getting errors/warnings.  Look at the screen shot below, for the new “video” tag which is showing up in intellisense (video is a part of the new HTML5 specifications)     note that, you still need to hook up the <!DOCTYPE html /> on the top manually as it doesn’t change automatically  (from the default XHTML 1.0 strict) when you create a new page. Also, the new input type tags in HTML5 are also supported One, can also use the <asp:TextBox type=”email” which would in turn generate the <input type=”email”> markup when the page is rendered.  In fact, as of SP1 beta, this is the only way to put the new input type tags with the runat=”server” attribute (otherwise you will get the parser error mentioned above.  This issue would be fixed by the final release of SP1 beta) Going further, there may be more support for having server tags for some of the common HTML5 elements, but this is work in progress currently. So, other than not having runat=”server” support for the new HTML5  input tags, you can pretty much build and target HTML5 websites with Visual Studio 2010 SP1 Beta, today.  For those who are running Visual Studio 2008, you also have the “HTML5 intellisense for Visual Studio 2010 and 2008” available for download, from http://visualstudiogallery.msdn.microsoft.com/d771cbc8-d60a-40b0-a1d8-f19fc393127d/ Note that, if you are running Visual Studio 2010, the recommended approach is to install the SP1 beta which would be the way forward for HTML5 support in Visual Studio. Of course, you need to test these on a browser supporting HTML5 such as IE9 Beta or Chrome or FireFox 4.  You can download IE9 Beta from here You can also follow the Visual Web Developer Team Blog for more updates on the stuff they are building. Cheers !!!

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  • SSIS: Building SQL databases on-the-fly using concatenated SQL scripts

    - by DrJohn
    Over the years I have developed many techniques which help automate the whole SQL Server build process. In my current process, where I need to build entire OLAP data marts on-the-fly, I make regular use of a simple but very effective mechanism to concatenate all the SQL Scripts together from my SSMS (SQL Server Management Studio) projects. This proves invaluable because in two clicks I can redeploy an entire SQL Server database with all tables, views, stored procedures etc. Indeed, I can also use the concatenated SQL scripts with SSIS to build SQL Server databases on-the-fly. You may be surprised to learn that I often redeploy the database several times per day, or even several times per hour, during the development process. This is because the deployment errors are logged and you can quickly see where SQL Scripts have object dependency errors. For example, after changing a table structure you may have forgotten to change any related views. The deployment log immediately points out all the objects which failed to build so you can fix and redeploy the database very quickly. The alternative approach (i.e. doing changes in the database directly using the SSMS UI) would require you to check all dependent objects before making changes. The chances are that you will miss something and wonder why your app returns the wrong data – a common problem caused by changing a table without re-creating dependent views. Using SQL Projects in SSMS A great many developers fail to make use of SQL Projects in SSMS (SQL Server Management Studio). To me they are invaluable way of organizing your SQL Scripts. The screenshot below shows a typical SSMS solution made up of several projects – one project for tables, another for views etc. The key point is that the projects naturally fall into the right order in file system because of the project name. The number in the folder or file name ensures that the projects the SQL scripts are concatenated together in the order that they need to be executed. Hence the script filenames start with 100, 110 etc. Concatenating SQL Scripts To concatenate the SQL Scripts together into one file, I use notepad.exe to create a simple batch file (see example screenshot) which uses the TYPE command to write the content of the SQL Script files into a combined file. As the SQL Scripts are in several folders, I simply use several TYPE command multiple times and append the output together. If you are unfamiliar with batch files, you may not know that the angled bracket (>) means write output of the program into a file. Two angled brackets (>>) means append output of this program into a file. So the command-line DIR > filelist.txt would write the content of the DIR command into a file called filelist.txt. In the example shown above, the concatenated file is called SB_DDS.sql If, like me you place the concatenated file under source code control, then the source code control system will change the file's attribute to "read-only" which in turn would cause the TYPE command to fail. The ATTRIB command can be used to remove the read-only flag. Using SQLCmd to execute the concatenated file Now that the SQL Scripts are all in one big file, we can execute the script against a database using SQLCmd using another batch file as shown below: SQLCmd has numerous options, but the script shown above simply executes the SS_DDS.sql file against the SB_DDS_DB database on the local machine and logs the errors to a file called SB_DDS.log. So after executing the batch file you can simply check the error log to see if your database built without a hitch. If you have errors, then simply fix the source files, re-create the concatenated file and re-run the SQLCmd to rebuild the database. This two click operation allows you to quickly identify and fix errors in your entire database definition.Using SSIS to execute the concatenated file To execute the concatenated SQL script using SSIS, you simply drop an Execute SQL task into your package and set the database connection as normal and then select File Connection as the SQLSourceType (as shown below). Create a file connection to your concatenated SQL script and you are ready to go.   Tips and TricksAdd a new-line at end of every fileThe most common problem encountered with this approach is that the GO statement on the last line of one file is placed on the same line as the comment at the top of the next file by the TYPE command. The easy fix to this is to ensure all your files have a new-line at the end.Remove all USE database statementsThe SQLCmd identifies which database the script should be run against.  So you should remove all USE database commands from your scripts - otherwise you may get unintentional side effects!!Do the Create Database separatelyIf you are using SSIS to create the database as well as create the objects and populate the database, then invoke the CREATE DATABASE command against the master database using a separate package before calling the package that executes the concatenated SQL script.    

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  • What IDE to use for Python

    - by husayt
    As a Python newbie, it is interesting to know what IDE's ("GUIs/editors") others use for Python coding. If you can just give the name (e.g. Textpad, Eclipse ..) that will be enough. If it is already mentioned, you can just vote for it. But if you can also give some more comparative information, that will be much appreciated. Thanks. Update: Results so far PyDev with Eclipse (CP, F, AC, PD, EM, SI, MLS, UML, SC, UT, LN, CF, BM) Komodo (CP, C/F, MLS, PD, AC, SC, SI, BM, LN, CF, CT) Emacs (CP, F, AC, MLS, PD, EM, SC, SI, BM, LN, CF, CT, UT, UML) Vim (CP, F, AC, MLS, SI, BM, LN, CF ) TextMate (Mac, CT, CF, MLS, SI, BM, LN) Gedit (Linux, F, AC, MLS, BM, LN, CT [sort of]) Idle (CP, F, AC) PIDA (Linux, CP, F, AC, MLS, SI, BM, LN, CF)(VIM Based) NotePad++ (Windows) BlueFish (Linux) JEdit (CP, F, BM, LN, CF, MLS) E-Texteditor (TextMate Clone for Windows) WingIde (CP, C, AC, MLS (support for C), PD, EM, SC, SI, BM, LN, CF, CT, UT) Eric Ide (CP, F, AC, PD, EM, SI, LN, CF, UT) Pyscripter (Windows, F, AC, PD, EM, SI, LN, CT, UT) ConTEXT (Windows, C) SPE (F, AC, UML) SciTE (CP, F, MLS, EM, BM, LN, CF, CT, SH) Zeus (W, C, BM, LN, CF, SI, SC, CT) NetBeans (CP, F, PD, UML, AC, MLS, SC, SI, BM, LN, CF, CT, UT, RAD) DABO (CP) BlackAdder (C, CP, CF, SI) PythonWin (W, F, AC, PD, SI, BM, CF) Geany (CP, F, very limited AC, MLS, SI, BM, LN, CF) UliPad (CP, F, AC, PD, MLS, SI, LI, CT, UT, BM) Boa Constructor (CP, F, AC, PD, EM, SI, BM, LN, UML, CF, CT) ScriptDev (W, C, AC, MLS, PD, EM, SI, BM, LN, CF, CT) Spider (CP, F, AC) Editra (CP, F, AC, MLS, SC, SI, BM, LN, CF) Pfaide (Windows, C, AC, MLS, SI, BM, LN, CF, CT) KDevelop (CP, F, MLS, SC, SI, BM, LN, CF) Acronyms used: CP - Cross Platfom C - Commercial F - Free AC - Automatic Code-completion MLS - Multi-Language Support PD - Integrated Python Debugging EM - ErrorMarkup SC - Source Control integration SI - Smart Indent BM - Bracket Matching LN - Line Numbering UML - UML editing / viewing CF - Code Folding CT - Code Templates UT - Unit Testing UID - Gui Designer (e.g. QT, Eric, ..) DB - integrated database support RAD - Rapid app development support I don't mention basics like Syntax highlighting as I expect these by default. This is a just dry list reflecting your feedback and comments, I am not advocating any of these tools. I will keep updating this list as you keep posting your answers. PS. Can you help me to add features of the above editors to the list (like autocomplete, debugging, or etc)?

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  • Regular exp to validate email in C

    - by Liju Mathew
    Hi, We need to write a email validation program in C. We are planning to use GNU Cregex.h) regular expression. The regular expression we prepared is [a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])? But the below code is failing while compiling the regex. #include <stdio.h> #include <regex.h> int main(const char *argv, int argc) { const char *reg_exp = "[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?"; int status = 1; char email[71]; regex_t preg; int rc; printf("The regex = %s\n", reg_exp); rc = regcomp(&preg, reg_exp, REG_EXTENDED|REG_NOSUB); if (rc != 0) { if (rc == REG_BADPAT || rc == REG_ECOLLATE) fprintf(stderr, "Bad Regex/Collate\n"); if (rc == REG_ECTYPE) fprintf(stderr, "Invalid Char\n"); if (rc == REG_EESCAPE) fprintf(stderr, "Trailing \\\n"); if (rc == REG_ESUBREG || rc == REG_EBRACK) fprintf(stderr, "Invalid number/[] error\n"); if (rc == REG_EPAREN || rc == REG_EBRACE) fprintf(stderr, "Paren/Bracket error\n"); if (rc == REG_BADBR || rc == REG_ERANGE) fprintf(stderr, "{} content invalid/Invalid endpoint\n"); if (rc == REG_ESPACE) fprintf(stderr, "Memory error\n"); if (rc == REG_BADRPT) fprintf(stderr, "Invalid regex\n"); fprintf(stderr, "%s: Failed to compile the regular expression:%d\n", __func__, rc); return 1; } while (status) { fgets(email, sizeof(email), stdin); status = email[0]-48; rc = regexec(&preg, email, (size_t)0, NULL, 0); if (rc == 0) { fprintf(stderr, "%s: The regular expression is a match\n", __func__); } else { fprintf(stderr, "%s: The regular expression is not a match: %d\n", __func__, rc); } } regfree(&preg); return 0; } The regex compilation is failing with the below error. The regex = [a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])? Invalid regex main: Failed to compile the regular expression:13 What is the cause of this error? Whether the regex need to be modified? Thanks, Mathew Liju

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  • Directly Jump to another C++ function

    - by maligree
    I'm porting a small academic OS from TriCore to ARM Cortex (Thumb-2 instruction set). For the scheduler to work, I sometimes need to JUMP directly to another function without modifying the stack nor the link register. On TriCore (or, rather, on tricore-g++), this wrapper template (for any three-argument-function) works: template< class A1, class A2, class A3 > inline void __attribute__((always_inline)) JUMP3( void (*func)( A1, A2, A3), A1 a1, A2 a2, A3 a3 ) { typedef void (* __attribute__((interrupt_handler)) Jump3)( A1, A2, A3); ( (Jump3)func )( a1, a2, a3 ); } //example for using the template: JUMP3( superDispatch, this, me, next ); This would generate the assembler instruction J (a.k.a. JUMP) instead of CALL, leaving the stack and CSAs unchanged when jumping to the (otherwise normal) C++ function superDispatch(SchedulerImplementation* obj, Task::Id from, Task::Id to). Now I need an equivalent behaviour on ARM Cortex (or, rather, for arm-none-linux-gnueabi-g++), i.e. generate a B (a.k.a. BRANCH) instruction instead of BLX (a.k.a. BRANCH with link and exchange). But there is no interrupt_handler attribute for arm-g++ and I could not find any equivalent attribute. So I tried to resort to asm volatile and writing the asm code directly: template< class A1, class A2, class A3 > inline void __attribute__((always_inline)) JUMP3( void (*func)( A1, A2, A3), A1 a1, A2 a2, A3 a3 ) { asm volatile ( "mov.w r0, %1;" "mov.w r1, %2;" "mov.w r2, %3;" "b %0;" : : "r"(func), "r"(a1), "r"(a2), "r"(a3) : "r0", "r1", "r2" ); } So far, so good, in my theory, at least. Thumb-2 requires function arguments to be passed in the registers, i.e. r0..r2 in this case, so it should work. But then the linker dies with undefined reference to `r6' on the closing bracket of the asm statement ... and I don't know what to make of it. OK, I'm not the expert in C++, and the asm syntax is not very straightforward... so has anybody got a hint for me? A hint to the correct __attribute__ for arm-g++ would be one way, a hint to fix the asm code would be another. Another way maybe would be to tell the compiler that a1..a3 should already be in the registers r0..r2 when the asm statement is entered (I looked into that a bit, but did not find any hint).

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  • Delete last 3 lines within while ((line = r.ReadLine()) != null) but not open a new text file to delete the lines?

    - by user1473672
    This is the code I've seen so far to delete last 3 lines in a text file, but it's required to determine string[] lines = File.ReadAllLines(); which is nt necessary for me to do so. string[] lines = File.ReadAllLines(@"C:\\Users.txt"); StringBuilder sb = new StringBuilder(); int count = lines.Length - 3; // except last 3 lines for (int s = 0; s < count; s++) { sb.AppendLine(lines[s]); } The code works well, but I don't wanna re-read the file as I've mentioned the streamreader above : using (StreamReader r = new StreamReader(@"C:\\Users.txt")) Im new to C#, as far as I know, after using streamreader, and if I wanna modify the lines, I have to use this : while ((line = r.ReadLine()) != null) { #sample codes inside the bracket line = line.Replace("|", ""); line = line.Replace("MY30", ""); line = line.Replace("E", ""); } So, is there any way to delete the last 3 lines in the file within the "while ((line = r.ReadLine()) != null)" ?? I have to delete lines, replace lines and a few more modications in one shot, so I can't keep opening/reading the same text file again and again to modify the lines. I hope the way I ask is understable for you guys .< Plz help me, I know the question sounds simple but I've searched so many ways to solve it but failed =( So far, my code is : using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; namespace ConsoleApplication11 { public class Read { static void Main(string[] args) { string tempFile = Path.GetTempFileName(); using (StreamReader r = new StreamReader(@"C:\\Users\SAP Report.txt")) { using (StreamWriter sw = new StreamWrite (@"C:\\Users\output2.txt")) { string line; while ((line = r.ReadLine()) != null) { line = line.Replace("|", ""); line = line.Replace("MY30", ""); line = line.Replace("E", ""); line = System.Text.RegularExpressions.Regex.Replace(line, @"\s{2,}", " "); sw.WriteLine(line); } } } } } } Now my next task is to delete the last 3 lines in the file after these codes, and I need help on this one. Thank you.

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  • MVC 3 AdditionalMetadata Attribute with ViewBag to Render Dynamic UI

    - by Steve Michelotti
    A few months ago I blogged about using Model metadata to render a dynamic UI in MVC 2. The scenario in the post was that we might have a view model where the questions are conditionally displayed and therefore a dynamic UI is needed. To recap the previous post, the solution was to use a custom attribute called [QuestionId] in conjunction with an “ApplicableQuestions” collection to identify whether each question should be displayed. This allowed me to have a view model that looked like this: 1: [UIHint("ScalarQuestion")] 2: [DisplayName("First Name")] 3: [QuestionId("NB0021")] 4: public string FirstName { get; set; } 5: 6: [UIHint("ScalarQuestion")] 7: [DisplayName("Last Name")] 8: [QuestionId("NB0022")] 9: public string LastName { get; set; } 10: 11: [UIHint("ScalarQuestion")] 12: [QuestionId("NB0023")] 13: public int Age { get; set; } 14: 15: public IEnumerable<string> ApplicableQuestions { get; set; } At the same time, I was able to avoid repetitive IF statements for every single question in my view: 1: <%: Html.EditorFor(m => m.FirstName, new { applicableQuestions = Model.ApplicableQuestions })%> 2: <%: Html.EditorFor(m => m.LastName, new { applicableQuestions = Model.ApplicableQuestions })%> 3: <%: Html.EditorFor(m => m.Age, new { applicableQuestions = Model.ApplicableQuestions })%> by creating an Editor Template called “ScalarQuestion” that encapsulated the IF statement: 1: <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %> 2: <%@ Import Namespace="DynamicQuestions.Models" %> 3: <%@ Import Namespace="System.Linq" %> 4: <% 5: var applicableQuestions = this.ViewData["applicableQuestions"] as IEnumerable<string>; 6: var questionAttr = this.ViewData.ModelMetadata.ContainerType.GetProperty(this.ViewData.ModelMetadata.PropertyName).GetCustomAttributes(typeof(QuestionIdAttribute), true) as QuestionIdAttribute[]; 7: string questionId = null; 8: if (questionAttr.Length > 0) 9: { 10: questionId = questionAttr[0].Id; 11: } 12: if (questionId != null && applicableQuestions.Contains(questionId)) { %> 13: <div> 14: <%: Html.Label("") %> 15: <%: Html.TextBox("", this.Model)%> 16: </div> 17: <% } %> You might want to go back and read the full post in order to get the full context. MVC 3 offers a couple of new features that make this scenario more elegant to implement. The first step is to use the new [AdditionalMetadata] attribute which, so far, appears to be an under appreciated new feature of MVC 3. With this attribute, I don’t need my custom [QuestionId] attribute anymore - now I can just write my view model like this: 1: [UIHint("ScalarQuestion")] 2: [DisplayName("First Name")] 3: [AdditionalMetadata("QuestionId", "NB0021")] 4: public string FirstName { get; set; } 5:   6: [UIHint("ScalarQuestion")] 7: [DisplayName("Last Name")] 8: [AdditionalMetadata("QuestionId", "NB0022")] 9: public string LastName { get; set; } 10:   11: [UIHint("ScalarQuestion")] 12: [AdditionalMetadata("QuestionId", "NB0023")] 13: public int Age { get; set; } Thus far, the documentation seems to be pretty sparse on the AdditionalMetadata attribute. It’s buried in the Other New Features section of the MVC 3 home page and, after showing the attribute on a view model property, it just says, “This metadata is made available to any display or editor template when a product view model is rendered. It is up to you to interpret the metadata information.” But what exactly does it look like for me to “interpret the metadata information”? Well, it turns out it makes the view much easier to work with. Here is the re-implemented ScalarQuestion template updated for MVC 3 and Razor: 1: @{ 2: object questionId; 3: ViewData.ModelMetadata.AdditionalValues.TryGetValue("QuestionId", out questionId); 4: if (ViewBag.applicableQuestions.Contains((string)questionId)) { 5: <div> 6: @Html.LabelFor(m => m) 7: @Html.TextBoxFor(m => m) 8: </div> 9: } 10: } So we’ve gone from 17 lines of code (in the MVC 2 version) to about 7-8 lines of code here. The first thing to notice is that in MVC 3 we now have a property called “AdditionalValues” that hangs off of the ModelMetadata property. This is automatically populated by any [AdditionalMetadata] attributes on the property. There is no more need for me to explicitly write Reflection code to GetCustomAttributes() and then check to see if those attributes were present. I can just call TryGetValue() on the dictionary to see if they were present. Secondly, the “applicableQuestions” anonymous type that I passed in from the calling view – in MVC 3 I now have a dynamic ViewBag property where I can just “dot into” the applicableQuestions with a nicer syntax than dictionary square bracket syntax. And there’s no problems calling the Contains() method on this dynamic object because at runtime the DLR has resolved that it is a generic List<string>. At this point you might be saying that, yes the view got much nicer than the MVC 2 version, but my view model got slightly worse.  In the previous version I had a nice [QuestionId] attribute but now, with the [AdditionalMetadata] attribute, I have to type the string “QuestionId” for every single property and hope that I don’t make a typo. Well, the good news is that it’s easy to create your own attributes that can participate in the metadata’s additional values. The key is that the attribute must implement that IMetadataAware interface and populate the AdditionalValues dictionary in the OnMetadataCreated() method: 1: public class QuestionIdAttribute : Attribute, IMetadataAware 2: { 3: public string Id { get; set; } 4:   5: public QuestionIdAttribute(string id) 6: { 7: this.Id = id; 8: } 9:   10: public void OnMetadataCreated(ModelMetadata metadata) 11: { 12: metadata.AdditionalValues["QuestionId"] = this.Id; 13: } 14: } This now allows me to encapuslate my “QuestionId” string in just one place and get back to my original attribute which can be used like this: [QuestionId(“NB0021”)]. The [AdditionalMetadata] attribute is a powerful and under-appreciated new feature of MVC 3. Combined with the dynamic ViewBag property, you can do some really interesting things with your applications with less code and ceremony.

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  • The last MVVM you'll ever need?

    - by Nuri Halperin
    As my MVC projects mature and grow, the need to have some omnipresent, ambient model properties quickly emerge. The application no longer has only one dynamic pieced of data on the page: A sidebar with a shopping cart, some news flash on the side – pretty common stuff. The rub is that a controller is invoked in context of a single intended request. The rest of the data, even though it could be just as dynamic, is expected to appear on it's own. There are many solutions to this scenario. MVVM prescribes creating elaborate objects which expose your new data as a property on some uber-object with more properties exposing the "side show" ambient data. The reason I don't love this approach is because it forces fairly acute awareness of the view, and soon enough you have many MVVM objects laying around, and views have to start doing null-checks in order to ensure you really supplied all the values before binding to them. Ick. Just as unattractive is the ViewData dictionary. It's not strongly typed, and in both this and the MVVM approach someone has to populate these properties – n'est pas? Where does that live? With MVC2, we get the formerly-futures  feature Html.RenderAction(). The feature allows you plant a line in a view, of the format: <% Html.RenderAction("SessionInterest", "Session"); %> While this syntax looks very clean, I can't help being bothered by it. MVC was touting a very strong separation of concerns, the Model taking on the role of the business logic, the controller handling route and performing minimal view-choosing operations and the views strictly focused on rendering out angled-bracket tags. The RenderAction() syntax has the view calling some controller and invoking it inline with it's runtime rendering. This – to my taste – embeds too much  knowledge of controllers into the view's code – which was allegedly forbidden.  The one way flow "Controller Receive Data –> Controller invoke Model –> Controller select view –> Controller Hand data to view" now gets a "View calls controller and gets it's own data" which is not so one-way anymore. Ick. I toyed with some other solutions a bit, including some base controllers, special view classes etc. My current favorite though is making use of the ExpandoObject and dynamic features with C# 4.0. If you follow Phil Haack or read a bit from David Heyden you can see the general picture emerging. The game changer is that using the new dynamic syntax, one can sprout properties on an object and make use of them in the view. Well that beats having a bunch of uni-purpose MVVM's any day! Rather than statically exposed properties, we'll just use the capability of adding members at runtime. Armed with new ideas and syntax, I went to work: First, I created a factory method to enrich the focuse object: public static class ModelExtension { public static dynamic Decorate(this Controller controller, object mainValue) { dynamic result = new ExpandoObject(); result.Value = mainValue; result.SessionInterest = CodeCampBL.SessoinInterest(); result.TagUsage = CodeCampBL.TagUsage(); return result; } } This gives me a nice fluent way to have the controller add the rest of the ambient "side show" items (SessionInterest, TagUsage in this demo) and expose them all as the Model: public ActionResult Index() { var data = SyndicationBL.Refresh(TWEET_SOURCE_URL); dynamic result = this.Decorate(data); return View(result); } So now what remains is that my view knows to expect a dynamic object (rather than statically typed) so that the ASP.NET page compiler won't barf: <%@ Page Language="C#" Title="Ambient Demo" MasterPageFile="~/Views/Shared/Ambient.Master" Inherits="System.Web.Mvc.ViewPage<dynamic>" %> Notice the generic ViewPage<dynamic>. It doesn't work otherwise. In the page itself, Model.Value property contains the main data returned from the controller. The nice thing about this, is that the master page (Ambient.Master) also inherits from the generic ViewMasterPage<dynamic>. So rather than the page worrying about all this ambient stuff, the side bars and panels for ambient data all reside in a master page, and can be rendered using the RenderPartial() syntax: <% Html.RenderPartial("TagCloud", Model.SessionInterest as Dictionary<string, int>); %> Note here that a cast is necessary. This is because although dynamic is magic, it can't figure out what type this property is, and wants you to give it a type so its binder can figure out the right property to bind to at runtime. I use as, you can cast if you like. So there we go – no violation of MVC, no explosion of MVVM models and voila – right? Well, I could not let this go without a tweak or two more. The first thing to improve, is that some views may not need all the properties. In that case, it would be a waste of resources to populate every property. The solution to this is simple: rather than exposing properties, I change d the factory method to expose lambdas - Func<T> really. So only if and when a view accesses a member of the dynamic object does it load the data. public static class ModelExtension { // take two.. lazy loading! public static dynamic LazyDecorate(this Controller c, object mainValue) { dynamic result = new ExpandoObject(); result.Value = mainValue; result.SessionInterest = new Func<Dictionary<string, int>>(() => CodeCampBL.SessoinInterest()); result.TagUsage = new Func<Dictionary<string, int>>(() => CodeCampBL.TagUsage()); return result; } } Now that lazy loading is in place, there's really no reason not to hook up all and any possible ambient property. Go nuts! Add them all in – they won't get invoked unless used. This now requires changing the signature of usage on the ambient properties methods –adding some parenthesis to the master view: <% Html.RenderPartial("TagCloud", Model.SessionInterest() as Dictionary<string, int>); %> And, of course, the controller needs to call LazyDecorate() rather than the old Decorate(). The final touch is to introduce a convenience method to the my Controller class , so that the tedium of calling Decorate() everywhere goes away. This is done quite simply by adding a bunch of methods, matching View(object), View(string,object) signatures of the Controller class: public ActionResult Index() { var data = SyndicationBL.Refresh(TWEET_SOURCE_URL); return AmbientView(data); } //these methods can reside in a base controller for the solution: public ViewResult AmbientView(dynamic data) { dynamic result = ModelExtension.LazyDecorate(this, data); return View(result); } public ViewResult AmbientView(string viewName, dynamic data) { dynamic result = ModelExtension.LazyDecorate(this, data); return View(viewName, result); } The call to AmbientView now replaces any call the View() that requires the ambient data. DRY sattisfied, lazy loading and no need to replace core pieces of the MVC pipeline. I call this a good MVC day. Enjoy!

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