Search Results

Search found 5101 results on 205 pages for 'expression trees'.

Page 75/205 | < Previous Page | 71 72 73 74 75 76 77 78 79 80 81 82  | Next Page >

  • To call SelectMany dynamically in the way of System.Linq.Dynamic

    - by user341127
    In System.Linq.Dynamic, there are a few methods to form Select, Where and other Linq statements dynamically. But there is no for SelectMany. The method for Select is as the following: public static IQueryable Select(this IQueryable source, string selector, params object[] values) { if (source == null) throw new ArgumentNullException("source"); if (selector == null) throw new ArgumentNullException("selector"); LambdaExpression lambda = DynamicExpression.ParseLambda(source.ElementType, null, selector, values); IQueryable result = source.Provider.CreateQuery( Expression.Call( typeof(Queryable), "Select", new Type[] { source.ElementType, lambda.Body.Type }, source.Expression, Expression.Quote(lambda))); return result; } I tried to modify the above code, after hours working, I couldn't find a way out. Any suggestions are welcome. Ying

    Read the article

  • Infix to Postfix and unary/binary operators

    - by Jaapjan
    I have a piece of code that converts an infix expression to an expression tree in memory. This works just fine. There's just one small trouble. I just connect work out how to involve the unary operators correctly (the right associative ones). With the following infix expression : +1 + +2 - -3 - -4 I would expect an RPN of: 1+2++3-4-- Yet, none of the online infix-post converters I can find handle this example in the way I would expect. Does anyone have a clear explanation of handling right associative operators, specifically the binary ones that can be mistaken for the unary ones?

    Read the article

  • varchar comparison in SQL Server

    - by Ram
    I am looking for some SQL varchar comparison function like C# string.compare (we can ignore case for now, should return zero when the character expression are same and a non zero expression when they are different) Basically I have some alphanumeric column in one table which needs to be verified in another table. I cannot do select A.col1 - B.col1 from (query) as "-" operator cannot be applied on character expressions I cannot cast my expression as int (and then do a difference/subtraction) as it fails select cast ('ASXT000R' as int) Conversion failed when converting varchar 'ASXT000R' to int Soundex would not do it as soundex is same for 2 similar strings Difference would not do it as select difference('abc','ABC') = 4 (as per msdn, difference is the difference in the soundex of 2 character expressions and difference =4 implies least different) Is there any other way of doing it ?

    Read the article

  • Help using Horner's rule and Hash Functions in JAVA?

    - by Matt
    I am trying to use Horner's rule to convert words to integers. I understand how it works and how if the word is long, it may cause an overflow. My ultimate goal is to use the converted integer in a hash function h(x)=x mod tableSize. My book suggests, because of the overflow, you could "apply the mod operator after computing each parenthesized expression in Horner's rule." I don't exactly understand what they mean by this. Say the expression looks like this: ((14*32+15)*32+20)*32+5 Do I take the mod tableSize after each parenthesized expression and add them together? What would it look like with this hash function and this example of Horner's rule?

    Read the article

  • Java Regex for matching quoted string with escaped quotes

    - by kayahr
    I know there are already many questions like mine but I found no answer which works in Java. So I write a new question. I have text files with content like this: key1 = "This is a \"test\" text with escapes using '\\' characters"; key2 = 'It must work with \'single\' quotes and "double" quotes'; I need a regular expression which matches the values in the double-quotes (or single-quotes). This regular expression must support the escaped quotes and escaped backslashes. The regular expression must work with Java standard Pattern/Matcher classes.

    Read the article

  • How do I mix functions in complex SSRS expressions?

    - by Boydski
    I'm writing a report against a data repository that has null values within some of the columns. The problem is building expressions is as temperamental as a hormonal old lady and doesn't like my mixing of functions. Here's an expression I've written that does not work if the data in the field is null/nothing: =IIF( IsNumeric(Fields!ADataField.Value), RunningValue( IIF( DatePart("q", Fields!CreatedOn.Value) = "2", Fields!ADataField.Value, 0 ), Sum, Nothing ), Sum(0) ) (Pseudocode) "If the data is valid and if the data was created in the second quarter of the year, add it to the overall Sum, otherwise, add zero to the sum." Looks pretty straight forward. And the individual pieces of the expression work by themselves. IE: IsNumeric(), DatePart(), etc. But when I put them all together, the expression throws an error. I've attempted about every permutation of what's shown above, all to no avail. Null values in Fields!ADataField.Value cause errors. Thoughts?

    Read the article

  • Exchange cmdlets from c#

    - by poffio
    Hi to all, i need to run exchange cmdlets from a c# console application. i followed with success the guide from http://msdn.microsoft.com/en-us/library/bb332449.aspx but only for the basic command and one parameter. the cmdlets i need to run is: Get-MailboxStatistics -server evs | Select servername, StorageGroupName,databasename,@{expression={$_.TotalItemSize.value.ToKB()}},ItemCount,mailboxguid In detail i cannot specify the field that i need after the select "command" and i don't know how can i pass to cmdlets, the expression "@{expression={$_.TotalItemSize.value.ToKB()}}". Is there a way to do it in managed code ? Thank you. Fabio.

    Read the article

  • StremReader.ReadToEnd() returning an empty string

    - by axk
    I have a method private static String DecompressAndDecode(byte[] data) { GZipStream decompressor = new GZipStream(new MemoryStream(data), CompressionMode.Decompress); StreamReader decompressed = new StreamReader(decompressor, Encoding.UTF8); String result = decompressed.ReadToEnd(); return result; } I have some GZipped text as input and the result is supposed to be a String representation of this text. The problem is that the method returns an empty string. What is puzzling me is that when I step trough the method in debug mode and reach the return statement the result variable is an empty string but if I create a watch for the decompressed.ReadToEnd() expression it returns me the text. What I would expect at this point is the result variable to contain the text and the decompressed.ReadToEnd() expression evaluating to an empty string. (Reevaluating the decompressed.ReadToEnd() expression returns an empty string as expected). There must be something obvious I'm missing here.

    Read the article

  • runtime loading of ValidateAntiForgeryToken Salt value

    - by p.campbell
    Consider an ASP.NET MVC application using the Salt parameter in the [ValidateAntiForgeryToken] directive. The scenario is such that the app will be used by many customers. It's not terribly desirable to have the Salt known at compile time. The current strategy is to locate the Salt value in the web.config. [ValidateAntiForgeryToken(Salt = Config.AppSalt)] //Config.AppSalt is a static property that reads the web.config. This leads to a compile-time exception suggesting that the Salt must be a const at compile time. An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type How can I modify the application to allow for a runtime loading of the Salt so that the app doesn't have to be re-salted and recompiled for each customer? Consider that the Salt won't change frequently, if at all, thereby removing the possibility of invalidating form

    Read the article

  • what does this C++ line of code mean "sol<?=f((1<<n)-1,i,0)+abs(P[i])*price;"

    - by KItis
    Could anyone help me to understand following line of code. sol I am studying an algorithm written using c++ and it has following operator " following is the error message returned. Hello.cpp: In function ‘int main()’: Hello.cpp:115: error: ‘memset’ was not declared in this scope Hello.cpp:142: error: expected primary-expression before ‘?’ token Hello.cpp:142: error: expected primary-expression before ‘=’ token Hello.cpp:142: error: expected ‘:’ before ‘;’ token Hello.cpp:142: error: expected primary-expression before ‘;’ token may be " Thanks in advance for the time you spent reading this post.

    Read the article

  • How can I build a Truth Table Generator?

    - by KingNestor
    I'm looking to write a Truth Table Generator as a personal project. There are several web-based online ones here and here. (Example screenshot of an existing Truth Table Generator) I have the following questions: How should I go about parsing expressions like: ((P = Q) & (Q = R)) = (P = R) Should I use a parser generator like ANTLr or YACC, or use straight regular expressions? Once I have the expression parsed, how should I go about generating the truth table? Each section of the expression needs to be divided up into its smallest components and re-built from the left side of the table to the right. How would I evaluate something like that? Can anyone provide me with tips concerning the parsing of these arbitrary expressions and eventually evaluating the parsed expression?

    Read the article

  • C# Lambda Problem

    - by Chris Klepeis
    Probably something simple, but as I'm new to lambda expressions, the problem evades me: m => m.contactID == contactID && m.primaryAddress == true && (m.addressTypeID == 2 || m.addressTypeID == 3) I tried to use that lambda expression but I receive an invalid operator. Is there a way to simplify this so that it would work? Edit: The equivolent sql query would be: SELECT * FROM Contact WHERE contactID = 3 AND primaryAddress = 1 AND (addressTypeID = 2 OR addressTypeID = 3) I have a repository function defined like so: public E Single(Expression<Func<E, bool>> where) { return objectSet.Single<E>(where); } I'm passing the lambda expression above into this function. Invalid operator error.

    Read the article

  • ANTLR lexing getting confused over '...' and floats

    - by Andy Hull
    I think the ANTLR lexer is treating my attempt at a range expression "1...3" as a float. The expression "x={1..3}" is coming out of the lexer as "x={.3}" when I used the following token definitions: FLOAT : ('0'..'9')+ ('.' '0'..'9'+)? EXPONENT? | ('.' '0'..'9')+ EXPONENT? ; AUTO : '...'; When I change FLOAT to just check for integers, as so: FLOAT : ('0'..'9')+; then the expression "x={1...3}" is tokenized correctly. Can anyone help me to fix this? Thanks!

    Read the article

  • Is it possible to have regexp that matches all valid regular expressions?

    - by Juha Syrjälä
    Is it possible to detect if a given string is valid regular expression, using just regular expressions? Say I have some strings, that may or may not be a valid regular expressions. I'd like to have a regular expression matches those string that correspond to valid regular expression. Is that possible? Or do I have use some higher level grammar (i.e. context free language) to detect this? Does it affect if I am using some extended version of regexps like Perl regexps? If that is possible, what the regexp matching regexp is?

    Read the article

  • How to access a String Array location in android?

    - by Vamsi Challa
    Android 2.3.3 This is my code... String[] expression = {""}; //globally declared as empty somewhere in the code below, I am trying to assign a string to it. expression[0] = "Hi"; I keep getting the following error... 12-08 22:12:19.063: E/AndroidRuntime(405): java.lang.ArrayIndexOutOfBoundsException Can someone help me with this.. Can we access the index 0, directly as i am doing? Actual Code ::: static int x = 0; // global declaration String[] assembledArray = {""}; // global declaration assembleArray(strSubString, expression.charAt(i)); //Passing string to the method //Method Implementation private void assembleArray(String strSubString, char charAt) { // TODO Auto-generated method stub assembledArray[x] = strSubString; assembledArray[x+1] = String.valueOf(charAt); x = x+2; }

    Read the article

  • Is Lightweight Code Generation (LCG) dead?

    - by Greg Beech
    In the .NET 2.0-3.5 frameworks, LCG (aka the DynamicMethod class) was a decent way to emit lightweight methods at runtime when no class structure was needed to support them. In .NET 4.0, expression trees now support statements and blocks, and as such appear to provide sufficient functionality to build just about any functionality you could require from such a method, and can be constructed in a much easier and safer way than directly emitting CIL op-codes. (This statement is borne from today's experimentation of converting some of our most complex LCG code to use expression tree building and compilation instead.) So is there any reason why one would use LCG in any new code? Is there anything it can do that expression trees cannot? Or is it now a 'dead' piece of functionality?

    Read the article

  • DisplayName attribute from Resources?

    - by Palantir
    Hello! I have a localized application, and I am wondering if it is possible to have the DisplayName for a certain model property set from a Resource. I'd like to do something like this: public class MyModel { [Required] [DisplayName(Resources.Resources.labelForName)] public string name{ get; set; } } But I can't to it, as the compiler says: "An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type" :( Are there any workarounds? I am outputting labels manually, but I need these for the validator output!

    Read the article

  • From my code, I can't trace the out of bounds exception.

    - by Matt
    public override Models.CalculationNode Parse(string expression) { var calNode = new Models.CalculationNode(); int i = expression.Length; char[] x = expression.ToCharArray(); string temp = ""; //Backwards assembly of the tree //Right Node while (!IsOperator(x[i]) && i > 0) { if (!x[i].Equals(' ')) temp = x[i] + temp; i--; } } It has been a while since I've used trees and I'm getting an out of bounds exception in the while loop.

    Read the article

  • NHibernate: how to do lookup a specific date

    - by Daoming Yang
    How I can lookup a specific date in Nhibernate? I'm currently using this to lookup one day's order. ICriteria criteria = SessionManager.CurrentSession.CreateCriteria(typeof(Order)) .Add(Expression.Between("DateCreated", date.Date.AddDays(-1), date.Date.AddDays(1))) .AddOrder(NHibernate.Criterion.Order.Desc("OrderID")); I tried the following code, but they did bring the data for me. Expression.Eq("DateCreated", date) Expression.Like("DateCreated", date) Note: The pass in date value will be like this 2010-04-03 00:00:00, The actual date value in the database will be like this 2010-03-13 11:17:16.000 Can anyone let me know how to do this? Many thanks.

    Read the article

  • NHibernate: how to do lookup a specific date in Nhibernate

    - by Daoming Yang
    How I can lookup a specific date in Nhibernate? I'm currently using this to lookup one day's order. ICriteria criteria = SessionManager.CurrentSession.CreateCriteria(typeof(Order)) .Add(Expression.Between("DateCreated", date.Date.AddDays(-1), date.Date.AddDays(1))) .AddOrder(NHibernate.Criterion.Order.Desc("OrderID")); I tried the following code, but they did bring the data for me. Expression.Eq("DateCreated", date) Expression.Like("DateCreated", date) Note: The pass in date value will be like this 2010-04-03 00:00:00, The actual date value in the database will be like this 2010-03-13 11:17:16.000 Can anyone let me know how to do this? Many thanks.

    Read the article

  • Formatting Field Declarations in Eclipse

    - by geeko
    Greetings Overflowers, Problem: public abstract class Filter { private long id; protected String expression; } how can I align fields automatically in Eclipse, such in: public abstract class Filter { private long id; protected String expression; } Note the space before long, thank you ! UPDATE: I cannot find a customization option to align types of class members (e.g.: long and String) under Eclipse formatter options. Yes, there is one to align names of class members (e.g.: id and expression) but not their types. Please, take a lock at this issue in my examples above. Any solution ?

    Read the article

  • Spaces around all hyphens in a string without double-up

    - by Dave
    I'm after a regex that puts spaces around each "-" in a string, eg. 02 jaguar-leopard, tiger-panther 08 would become 02 jaguar - leopard, tiger - panther 08 Note that if the "-" already has spaces around it, no changes are to be made, eg. 02 jaguar - leopard, tiger - panther 08 should not become 02 jaguar - leopard, tiger - panther 08 The number of hyphens are unknown in advance. Thanks for any ideas... Edit: I'm not actually using a language for this. I'm using Ant Renamer (a mass file renaming utility). There are two fields in the renamer GUI, "Expression" and "New name" to provide inputs. This is from the help file as an example: Swapping artist and title from mp3 file names: "Expression" = (.*) - (.*)\.mp3 "New name" = $2 - $1.mp3 Extract episode number and title from series video files with episode number as SnnEmm followed by title: "Expression" = Code\.Quantum\.S([0-9]{2})E([0-9]{2})\.(.*)\.FRENCH.XViD\.avi "New name" = Code Quantum - $1$2 - $3.avi

    Read the article

  • Cannot bind to list<T>.property or list<T>.item.property in details section of Telerik report

    - by fluf
    I have created a Telerik report and I am setting the datasource on runtime to an object with some properties and a List. I am using the properties in the page and report header sections and i want to use the list as the details. Now the problem is binding to the List's item properties in the details section. I have played around with the expression builder and it seems that i should access the properties like this : [=Fields.myList.Item.myProperty] when i run the program i get a nice big red rectangle with the following error : An error has occured while processing TextBox 'textBox28':Common Language Runtime detected an invalid program. I have tried to change different variants of expression which also gives me other errors [=Fields.myList.myPropery] An error has occured while processing TextBox 'textBox28': The expression contains object 'myProperty' that is not defined in the current context. The closest i have gotton was with the object it self, which outputs the object.toString() [=Fields.myList]

    Read the article

  • How do I test against a large number of regular expressions quickly and know which one matched?

    - by Jack
    I'm writing a program in .net where the user may provide a large number of regular expressions. For a given string, I need to figure out which regular expression matches that string (if more than one matches, I just need the first one that matches). However, if there are a large number of regular expressions this operation can take a very long time. I was somewhat hoping there would be something similar to flex for .net that would allow me to specify a large number of regular expressions yet quickly (O(n) according to Wikipedia for n = len(input string)) figure out which regular expression matches. Also, I would prefer not to implement my own regular expression engine :).

    Read the article

  • Regex to match a Java method signature

    - by nitesh
    I am having this particular requirement where a method has to be identified by different regular expressions for different components. For example, there need to be a regex for return parameter, one for method name, one for argument type and one for argument name. I was able to come up with an expression till this step as follows - ([^,]+) ([^,]+)\((([^,]+) ([^,]+))\) It works well for a method signature like - ReturnType foo(Arg parameter) The regular expression identifies ReturnType, foo, Arg and parameter separately. Now the problem is that a method can have no/one/multiple arguments separated by commas. I am not able to get a repeating expression for this. Help will be appreciated.

    Read the article

< Previous Page | 71 72 73 74 75 76 77 78 79 80 81 82  | Next Page >