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  • How to handle image/gif type response on client side using GWT

    - by user200340
    Hi all, I have a question about how to handle image/gif type response on client side, any suggestion will be great. There is a service which responds for retrieving image (only one each time at the moment) from database. The code is something like, JDBC Connection Construct MYSQL query. Execute query If has ResultSet, retrieve first one { //save image into Blob image, “img” is the only entity in the image table. image = rs.getBlob("img"); } response.setContentType("image/gif"); //set response type InputStream in = image.getBinaryStream(); //output Blob image to InputStream int bufferSize = 1024; //buffer size byte[] buffer = new byte[bufferSize]; //initial buffer int length =0; //read length data from inputstream and store into buffer while ((length = in.read(buffer)) != -1) { out.write(buffer, 0, length); //write into ServletOutputStream } in.close(); out.flush(); //write out The code on client side .... imgform.setAction(GWT.getModuleBaseURL() + "serviceexample/ImgRetrieve"); .... ClickListener { OnClick, then imgform.submit(); } formHandler { onSubmit, form validation onSubmitComplete ??????? //handle response, and display image **Here is my question, i had tried Image img = new Image(GWT.getHostPageBaseURL() +"serviceexample/ImgRetrieve"); mg.setSize("300", "300"); imgpanel.add(img); but i only got a non-displayed image with 300X300 size.** } So, how should i handle the responde in this case? Thanks,

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  • Is there a Firebug -vsdoc?

    - by David Murdoch
    If not, does anyone care to write one? I would do it myself...but I don't have time right now...maybe next week (unless someone beats me to it). If you are bored and want to compile the vsdoc: Here is the Firebug API. Here is an example vsdoc (jquery-1.4.1-vsdoc.js). I create the following because I kept typing cosnole instead of console. You can use it as a starting point (ish). console = { /// <summary> /// 1: The javascript console /// </summary> /// <returns type="Object" /> }; console.log = function (object) { /// <summary> /// Write to the console's log /// </summary> /// <returns type="null" /> /// <param name="object" type="Object"> /// Write the object to the console's log /// </param> };

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  • Socket Read In Multi-Threaded Application Returns Zero Bytes or EINTR (-1)

    - by user309670
    Hi. Am a c-coder for a while now - neither a newbie nor an expert. Now, I have a certain daemoned application in C on a PPC Linux. I use PHP's socket_connect as a client to connect to this service locally. The server uses epoll for concurrent connections via a Unix socket. A user submitted string is parsed for certain characters/words using strstr() and if found, spawns 4 joinable threads to different websites simultaneously. I use socket, connect, write and read, to interact with the said webservers via TCP on port 80 in each thread. All connections and writes seems successful. Reads to the webserver sockets fail however, with either (A) all 3 threads seem to hang, and only one thread returns -1 and errno is set to 104. The responding thread takes like 10 minutes - an eternity long:-(. *I read somewhere that the 104 (is EINTR) suggests that ...'the connection was reset by peer', or (B) 0 bytes from 3 threads, and only 1 of the 4 threads actually returns some data. Isn't the socket read/write thread-safe? Otherwise, use thread-safe (and reentrant) libc functions such as strtok_r, gethostbyname_r, etc. *I doubt that the said webhosts are actually resetting the connection, because when I run a single-threaded standalone (everything else equal) all things works perfectly right. There's a second problem too (oops), I can't write back to the client who connect to my epoll-ed Unix socket. My daemon application will hang and hog CPU 100% for ever. Yet nothing is written to the clients end. Am sure the client (a very typical PHP socket application) hasn't closed the connection whenever this is happening - no error(s) detected either. I cannot figure-out whatever is wrong even with Valgrind or GDB

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  • Python: For loop problem

    - by James
    I have a PSP page with html embedded. I need to place another for loop so i can insert another %s next to background-color: which will instert a appropriate colour to colour in the html table. For example i need to insert for z in colours so it can loop over the colours list and insert the correct colour. Where ever i try to insert the for loop it doesnt seem to work it most commonly colours each cell in the table 60 times then moves onto the next cell and repeats itself and crashes my web browser. The colours are held in a table called colours. code below: <table> <% s = ''.join(aa[i] for i in table if i in aa) for i in range(0, len(s), 60): req.write('<tr><td><TT>%04d</td>' % (i+1)); for k in s[i:i+60]: req.write('<TT><td><TT><font style="background-color:">%s<font></td>' % (k)); req.write('</TT></tr>') #end %> </table>

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  • How to implement a download for dynamic files in asp.net with masterpages

    - by Tim
    Hello, the title says it all. I have seen some similar questions on SO like this or this, but either i have overlooked something or my requirement is different, neither works. My situation is following: i have a Masterpage one of its contentpage is called MasterData.aspx MasterData has an asp.net ajax tabcontainer control with one usercontrol in every tabpanel these usercontrols(f.e. MD_Customer.ascx)hold the main content(like a normal page) they all have GridViews in it and i want to provide an Excel-Export-Button What i've tried is is to use an iframe like here. But the function that adds the iframe to the document gets never called and therefore i never see the save-as-dialog. Maybe this is caused by using a MasterPage. Does somebody has an idea on how to provide a button in an UpdatePanel that causes an async postback, so that i can generate a CSV dynamically in codebehind and write it to the response? Thank you in advance. aspx-markup: <asp:UpdatePanel ID="UpdGridInfo" runat="server" > <ContentTemplate> <asp:Label ID="LblInfo" Font-Underline="false" runat="server" CssClass="content" ></asp:Label>&nbsp;&nbsp; <asp:ImageButton ToolTip="export to Excel" style="vertical-align:bottom" ID="BtnExcelExport" ImageUrl="~/images/excel2007logo.png" runat="server" /> </ContentTemplate> </asp:UpdatePanel> and the BtnExportExcel codebehind handler(of course it cannot work to write the csv to the response of this page): Private Sub BtnExcelExport_Click(ByVal sender As Object, ByVal e As System.Web.UI.ImageClickEventArgs) Handles BtnExcelExport.Click Dim csv As String = tableToCsv(DirectCast(Me.GridSource, DataTable)) Response.AddHeader("Content-disposition", "attachment; filename=RuleConfigurationFile.csv") Response.ContentType = "application/octet-stream" Response.Write(csv) Response.End() End Sub

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  • jQuery ajax post of jpg image to .net webservice. Image results corrupted

    - by sosergio
    I have a phonegap jquery app that opens the camera and take a picture. I then POST this picture to a .net webservice, wich I've coded. I can't use phonegap FileTransfer because such isn't supported by Bada os, wich is a requirement. I believe I've successfully loaded the image from phonegap FileSystem API, I've attached it into an .ajax type:post, I've even received it from .net side, but when .net save the image into the server, the image results corrupted. It seems to me that two sides of the communication have different data type. Has anyone experience in this? Any help will be appreciated. This is my code: //PHONEGAP CAMERA ACCESS (summed up) navigator.camera.getPicture(onGetPictureSuccess, onGetPictureFail, { quality: 50, destinationType:Camera.DestinationType.FILE_URI }); window.resolveLocalFileSystemURI(imageURI, onResolveFileSystemURISuccess, onResolveFileSystemURIError); fileEntry.file(gotFileSuccess, gotFileError); new FileReader().readAsDataURL(file); //UPLOAD FILE function onDataReadSuccess(evt) { var image_data = evt.target.result; var filename = unique_id(); var filext = "jpg"; $.ajax({ type : 'POST', url : SERVICE_BASE_URL+"/fotos/"+filename+"?ext="+filext, cache: false, timeout: 100000, processData: false, data: image_data, contentType: 'image/jpeg', success : function(data) { console.log("Data Uploaded with success. Message: "+ data); $.mobile.hidePageLoadingMsg(); $.mobile.changePage("ok.html"); } }); } On my .net Web Service this is the method that gets invoked: public string FotoSave(string filename, string extension, Stream fileContent) { string filePath = HttpContext.Current.Server.MapPath("~/foto_data/") + "\\" + filename; FileStream writeStream = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.Write); int Length = 256; Byte[] buffer = new Byte[Length]; int bytesRead = readStream.Read(buffer, 0, Length); // write the required bytes while (bytesRead > 0) { writeStream.Write(buffer, 0, bytesRead); bytesRead = readStream.Read(buffer, 0, Length); } readStream.Close(); writeStream.Close(); }

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  • JAXB, how to marshal without a namespace

    - by Alvin
    I have a fairly large repetitive XML to create using JAXB. Storing the whole object in the memory then do the marshaling takes too much memory. Essentially, my XML looks like this: <Store> <item /> <item /> <item /> ..... </Store> Currently my solution to the problem is to "hard code" the root tag to an output stream, and marshal each of the repetitive element one by one: aOutputStream.write("<?xml version="1.0"?>") aOutputStream.write("<Store>") foreach items as item aMarshaller.marshall(item, aOutputStream) end aOutputStream.write("</Store>") aOutputStream.close() Somehow the JAXB generate the XML like this <Store xmlns="http://stackoverflow.com"> <item xmlns="http://stackoverflow.com"/> <item xmlns="http://stackoverflow.com"/> <item xmlns="http://stackoverflow.com"/> ..... </Store> Although this is a valid XML, but it just look ugly, so I'm wonder is there any way to tell the marshaller not to put namespace for the item elements? Or is there better way to use JAXB to serialize to XML chunk by chunk?

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  • SOAP web services in haskell?

    - by Dave
    I have to write a bunch of small web services. They must be defined by a WSDL and work via SOAP-RPC, in order to work with an existing workflow engine and service registry framework. I can, however, serve them on a service stack/platform of my choice. I'm presently writing them in Java, and it's not too bad. But I'm thinking my life might be easier if I was able to write these services in Haskell. Searching on Google, it looks like, once upon a time, someone else had the same idea and started a project called "HAIFA". However, it looks like HAIFA hasn't been maintained for some years, and I couldn't find any other frameworks supporting serving up services written in Haskell as SOAP web services. Does anyone know of any other frameworks that will allow me to easily write SOAP-based web services using Haskell? If not, has anyone done this manually (i.e., use XML libraries from hackage to process the incoming soap-rpc requests, and create soap-rpc compliant replies)? Was it difficult to do? Any gotchas? Was it worth the effort? Thanks in advance!

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  • copy files to nework path or Drive using python

    - by user218976
    hi , Mine is similar to this question. http://stackoverflow.com/questions/2042342/network-path-and-variables-in-python/2042376 The only difference is my network drive has a password protect with user name and password . I need to copy files to a samba share using python and verify it. if i manually login in then the code works but without logging in the shutil command does not work Thanks

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  • What's the difference between these LINQ queries ?

    - by SnAzBaZ
    I use LINQ-SQL as my DAL, I then have a project called DB which acts as my BLL. Various applications then access the BLL to read / write data from the SQL Database. I have these methods in my BLL for one particular table: public IEnumerable<SystemSalesTaxList> Get_SystemSalesTaxList() { return from s in db.SystemSalesTaxLists select s; } public SystemSalesTaxList Get_SystemSalesTaxList(string strSalesTaxID) { return Get_SystemSalesTaxList().Where(s => s.SalesTaxID == strSalesTaxID).FirstOrDefault(); } public SystemSalesTaxList Get_SystemSalesTaxListByZipCode(string strZipCode) { return Get_SystemSalesTaxList().Where(s => s.ZipCode == strZipCode).FirstOrDefault(); } All pretty straight forward I thought. Get_SystemSalesTaxListByZipCode is always returning a null value though, even when it has a ZIP Code that exists in that table. If I write the method like this, it returns the row I want: public SystemSalesTaxList Get_SystemSalesTaxListByZipCode(string strZipCode) { var salesTax = from s in db.SystemSalesTaxLists where s.ZipCode == strZipCode select s; return salesTax.FirstOrDefault(); } Why does the other method not return the same, as the query should be identical ? Note that, the overloaded Get_SystemSalesTaxList(string strSalesTaxID) returns a record just fine when I give it a valid SalesTaxID. Is there a more efficient way to write these "helper" type classes ? Thanks!

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  • Progressively stream the output of an ASP.NET page - or render a page outside of an HTTP request

    - by Evgeny
    I have an ASP.NET 2.0 page with many repeating blocks, including a third-party server-side control (so it's not just plain HTML). Each is quite expensive to generate, in terms of both CPU and RAM. I'm currently using a standard Repeater control for this. There are two problems with this simple approach: The entire page must be rendered before any of it is returned to the client, so the user must wait a long time before they see any data. (I write progress messages using Response.Write, so there is feedback, but no actual results.) The ASP.NET worker process must hold everything in memory at the same time. There is no inherent needs for this: once one block is processed it won't be changed, so it could be returned to the client and the memory could be freed. I would like to somehow return these blocks to the client one at a time, as each is generated. I'm thinking of extracting the stuff inside the Repeater into a separate page and getting it repeatedly using AJAX, but there are some complications involved in that and I wonder if there is some simper approach. Ideally I'd like to keep it as one page (from the client's point of view), but return it incrementally. Another way would be to do something similar, but on the server: still create a separate page, but have the server access it and then Response.Write() the HTML it gets to the response stream for the real client request. Is there a way to avoid an HTTP request here, though? Is there some ASP.NET method that would render a UserControl or a Page outside of an HTTP request and simply return the HTML to me as a string? I'm open to other ideas on how to do this as well.

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  • Python opening a file and putting list of names on separate lines

    - by Jeremy Borton
    I am trying to write a python program using Python 3 I have to open a text file and read a list of names, print the list, sort the list in alphabetical order and then finally re-print the list. There's a little more to it than that BUT the problem I am having is that I'm supposed to print the list of names with each name on a separate line Instead of printing each name on a separate line, it prints the list all on one line. How can I fix this? def main(): #create control loop keep_going = 'y' #Open name file name_file = open('names.txt', 'r') names = name_file.readlines() name_file.close() #Open outfile outfile = open('sorted_names.txt', 'w') index = 0 while index < len(names): names[index] = names[index].rstrip('\n') index += 1 #sort names print('original order:', names) names.sort() print('sorted order:', names) #write names to outfile for item in names: outfile.write(item + '\n') #close outfile outfile.close() #search names while keep_going == 'y' or keep_going == 'Y': search = input('Enter a name to search: ') if search in names: print(search, 'was found in the list.') keep_going = input('Would you like to do another search Y for yes: ') else: print(search, 'was not found.') keep_going = input('Would you like to do another search Y for yes: ') main()

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  • Fake serial communication under Linux

    - by kigurai
    I have an application where I want to simulate the connection between a device and a "modem". The device will be connected to a serial port and will talk to the software modem through that. For testing purposes I want to be able to use a mock software device to test send and receive data. Example Python code device = Device() modem = Modem() device.connect(modem) device.write("Hello") modem_reply = device.read() Now, in my final app I will just pass /dev/ttyS1 or COM1 or whatever for the application to use. But how can I do this in software? I am running Linux and application is written in Python. I have tried making a FIFO (mkfifo ~/my_fifo) and that does work, but then I'll need one FIFO for writing and one for reading. What I want is to open ~/my_fake_serial_port and read and write to that. I have also lpayed with the ptymodule, but can't get that to work either. I can get a master and slave file descriptor from pty.openpty() but trying to read or write to them only causes IOError Bad File Descriptor error message.

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  • How to make Entity Key Mapping in Entity Framework like sql's foreign key?

    - by programmerist
    I try to give entity map on my entity app. But how can I do it? I try to make it like below: var test = ( from k in Kartlar where k.Rehber..... above codes k.(can not see Rehber or not working ) if you are correct , i can write k.Rehber.ID and others. i can not write: from k in Kartlar where k.Rehber.ID = 123 //assuming that navigation property name is Rehbar and its primary key of Rehbar table is ID && k.Kampanya.ID = 345 //assuming that navigation property name is Kampanya and its primary //key of Kampanya table is ID && k.Birim.ID = 567 //assuming that navigation property name is Birim and its primary key of Birim table is ID select k images you can see: also: You should look : http://i42.tinypic.com/2nqyyc6.png I have a table it includes 3 foreign key field like that: My Table: Kartlar ID (Pkey) RehberID (Fkey) KampanyaID (Fkey) BrimID (Fkey) Name Detail How can i write entity query with LINQ ? select * from Kartlar where RehberID=123 and KampanyaID=345 and BrimID=567 BUT please be careful I can not see RehberID, KampanyaID, BrimID in entity they are foreign key. I should use entity key but how?

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  • BinaryFormatter in C# a good way to read files?

    - by mr-pac
    I want to read a binary file which was created outside of my program. One obvious way in C# to read a binary file is to define class representing the file and then use a BinaryReader and read from the file via the Read* methods and assign the return values to the class properties. What I don't like with the approach is that I manually have to write code that reads the file, although the defined structure represents how the file is stored. I also have to keep the order correct when I read. After looking a bit around I came across the BinaryFormatter which can automatically serialize and deserialze object in binary format. One great advantage would be that I can read and also write the file without creating additional code. However I wonder if this approach is good for files created from other programs on not just serialized .NET objects. Take for example a graphics format file like BMP. Would it be a good idea to read the file with a BinaryFormatter or is it better to manually and write via BinaryReader and BinaryWriter? Or are there any other approaches which suit better? I'am not looking for concrete examples but just for an advice what is the best way to implement that.

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  • Download file is blocked using WatiN even after modifying registry settings

    - by Mstechuser1
    I'm doing an IE automation using WatiN. When a file to be downloaded is clicked, I get the following in the Internet Explorer Information bar: To help protect your security, Internet Explorer has blocked this site from downloading files to you computer. I added a registry key to, HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap\Domains\ then a REG_DWORD value named "http" with value==2 as given in http://stackoverflow.com/questions/972345/programmatically-add-trusted-sites-to-internet-explorer but still facing same issues. Can some1 advice on this....

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  • Multi-reader IPC solution?

    - by gct
    I'm working on a framework in C++ (just for fun for now), that lets the user write plugins that use a standard API to stream data between each other. There's going to be three basic transport mechanisms for the data: files, sockets, and some kind of IPC piping system. The system is set up so that for the non-file transport, each stream can have multiple readers. IE once a server socket it setup, multiple computers can connect and stream the data. I'm a little stuck at the multi-reader IPC system though. All my plugins run in threads so they live in the same address space, so some kind of shared memory system would work fine, I was thinking I'd write my own circular buffer with a write pointer and read pointers chassing it around the buffer, but I have my doubts that I can achieve the same performance as something like linux pipes. I'm curious what people would suggest for a multi-reader solution to something like this? Is the overhead for pipes or domain sockets low enough that I could just open a connection to each reader and issue separate writes to each reader? This is intended to be significant volumes of data (tens of mega-samples/sec), so performance is a must.

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  • dynamic LinkButton OnClick event not working on ASP.Net

    - by user1004472
    I want to create dynamic LinkButton for image, <img> tag is not working dynamically so I am using LinkButton with image. I don't want to provide ID to LinkButton because I want to generate more LinkButton dynamically. I am using following code in Default.aspx <%@ Page Language="C#"%> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <script runat="server"> protected void Page_Load(object sender, EventArgs e) { Response.Write(@"<asp:LinkButton runat=""server"" OnClick=""btn_click""><img src=""close-icon (1).png"" /></asp:LinkButton>"); } public void btn_click(object sender, EventArgs e) { Response.Write("HELLO"); } </script> </head> <body> <form id="form1" runat="server"> <div> </div> </form> </body> </html> I also tried to write tag code in Default.aspx.cs file but not work. It's showing me following error. Error 1 'ASP.default_aspx' does not contain a definition for 'img_Click' and no extension method 'img_Click' accepting a first argument of type 'ASP.default_aspx' could be found (are you missing a using directive or an assembly reference?) Please help me to solve this problem.

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  • How can I refactor these script tags?

    - by Shpigford
    I have the following script tags in the <head> so that they don't prompt any security errors when going back and forth between SSL and non-SSL pages. But it just looks hairy. Any way I can combine them or reduce some of the code? <script type="text/javascript">document.write(["\<script src='",("https:" == document.location.protocol) ? "https://" : "http://","ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js' type='text/javascript'>\<\/script>"].join(''));</script> <script type="text/javascript">document.write(["\<script src='",("https:" == document.location.protocol) ? "https://" : "http://","html5shiv.googlecode.com/svn/trunk/html5.js' type='text/javascript'>\<\/script>"].join(''));</script> <script type="text/javascript">document.write(["\<script src='",("https:" == document.location.protocol) ? "https://" : "http://","use.typekit.com/12345.js' type='text/javascript'>\<\/script>"].join(''));</script>

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  • How do I make a page aware that the viewer is logged in or not?

    - by Joann
    I am building a membership site... I just got thru the login page and I can now login and logout. However that alone doesn't protect all my pages in the root.. How do I go about this? I'd like to set it up like so when the viewer isn't log-in, the page that's being opened would say "Log in first blah3x"... Any help pls??? :-(

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  • Low Level Console Input

    - by Soulseekah
    I'm trying to send commands to to the input of a cmd.exe application using the low level read/write console functions. I have no trouble reading the text (scraping) using the ReadConsole...() and WriteConsole() functions after having attached to the process console, but I've not figured out how to write for example "dir" and have the console interpret it as a sent command. Here's a bit of my code: CreateProcess(NULL, "cmd.exe", NULL, NULL, FALSE, CREATE_NEW_CONSOLE, NULL, NULL, &si, &pi); AttachConsole(pi.dwProcessId); strcpy(buffer, "dir"); WriteConsole(GetStdHandle(STD_INPUT_HANDLE), buffer, strlen(buffer), &charRead, NULL); STARTUPINFO attributes of the process are all set to zero, except, of course, the .cb attribute. Nothing changes on the screen, however I'm getting an Error 6: Invalid Handle returned from WriteConsole to STD_INPUT_HANDLE. If I write to (STD_OUTPUT_HANDLE) I do get my dir written on the screen, but nothing of course happens. I'm guessing SetConsoleMode() might be of help, but I've tried many mode combinations, nothing helped. I've also created a quick console application that waits for input (scanf()) and echoes back whatever goes in, didn't work. I've also tried typing into the scanf() promp and then peek into the input buffer using PeekConsoleInput(), returns 0, but the INPUT_RECORD array is empty. I'm aware that there is another way around this using WriteConsoleInput() to directly inject INPUT_RECORD structured events into the console, but this would be way too long, I'll have to send each keypress into it. I hope the question is clear. Please let me know if you need any further information. Thanks for your help.

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  • How to accept confirmation Automatically in PowerShell for Outlook

    - by user2919845
    How to accept confirmation Automatically in PowerShell for Outlook I have script for Export attachments from email from Outlook - see next It works correctly on one PC, but on another PC is there a problem: Outlook gives message and wants answer: Permit Denny Help If I manually click on Permit or Denny it works correctly. I want to automate it. Can you give me some suggestion how to do it in PowerShell? I have tried to set Outlook to not give this message but I didn’t success. My script: # <-- Script ---------> # script works with outlook Inbox folder # check if email have attachments with ".txt" and save those attachments to $filepath # path for exported files - attachments $filepath = "d:\Exported_files\" # create object outlook $o = New-Object -comobject outlook.application $n = $o.GetNamespace("MAPI") # $f - folder „dorucena posta“ 6 - Inbox $f = $n.GetDefaultFolder(6) # 6 - Inbox # select newest 10 emails, from it olny this one with attachments $f.Items| select -last 10| Where {$_.Attachments}| foreach { # process only unreaded mail if($_.unread -eq $True) { # processed mail set as read, not to process this mail again next day $_.unread = $False $SenderName = $_.SenderName Write-Host "Email from: ", $SenderName # process all attachments $_.attachments|foreach { $a = $_.filename If ($a.Contains(".txt")) { Write-Host $SenderName," ", $a # copy *.txt attachments to folder $filepath $_.saveasfile((Join-Path $filepath "$a")) } } } } Write-Host "Finish" # <------ End Script ---------------------------------->

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  • Learn Prolog Now! DCG Practice Example

    - by Timothy
    I have been progressing through Learn Prolog Now! as self-study and am now learning about Definite Clause Grammars. I am having some difficulty with one of the Practical Session's tasks. The task reads: The formal language anb2mc2mdn consists of all strings of the following form: an unbroken block of as followed by an unbroken block of bs followed by an unbroken block of cs followed by an unbroken block of ds, such that the a and d blocks are exactly the same length, and the c and d blocks are also exactly the same length and furthermore consist of an even number of cs and ds respectively. For example, ε, abbccd, and aaabbbbccccddd all belong to anb2mc2mdn. Write a DCG that generates this language. I am able to write rules that generate andn, b2mc2m, and even anb2m and c2mndn... but I can't seem to join all these rules into anb2mc2mdn. The following are my rules that can generate andn and b2mc2m. s1 --> []. s1 --> a,s1,d. a --> [a]. d --> [d]. s2 --> []. s2 --> c,c,s2,d,d. c --> [c]. d --> [d]. Is anb2mc2mdn really a CFG, and is it possible to write a DCG using only what was taught in the lesson (no additional arguments or code, etc)? If so, can anyone offer me some guidance how I can join these so that I can solve the given task?

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  • Anyone NOT using a Web Framework? Why?

    - by tom
    I'm well aware of the many reasons to use a web framework. I'm just wondering whether anyone out there is using absolutely no web framework whatsoever to develop their web projects. I would really love to know the reason(s) why you're not using a web framework. For the sake of this discussion, your programming language of choice does not matter. Some possibilities for discussion: You don't hide behind an ORM. You don't rely on any sort of templating system. You think MVC is a really nice TLA but lacks an essential vowel or two. No need for any additional javascript framework tomfoolery. You just write as much code as possible in your native programming language(s). Summary of reasons thus far: Language learning opportunities. Specific performance reasons (write-intensive transaction processing). Seeking more nuanced control over your data and applications (less abstraction). You're building your own framework! Prove to yourself that you can succeed (or fail) just like the big framework-building gurus. Integration issues with unpopular/legacy technologies (exotic databases or protocols come to mind). Big company, lots of code, no talent nor buy-in present to move to a web framework. Some frameworks really lock you in and cannot perpetually grow along with your needs. These few black sheep don't make it easy to jump outside of the framework, write some custom code, and easily jump back in. When you finally escape the asylum, you'll never look back.

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