You can do a directory list with a pattern to check for files

    string[] files = System.IO.Directory.GetFiles(path, &quot;*_peach.xml&quot;, System.IO.SearchOption.TopDirectoryOnly);
    if (files.Length &gt; 0)
    {
        //file exist
    }

If you&#39;re using .net framework 4 or above you could use [`Directory.EnumerateFiles`](http://msdn.microsoft.com/en-us/library/dd413233(v=vs.110).aspx)

    bool exist = Directory.EnumerateFiles(path, &quot;*_peach.xml&quot;).Any();

This could be more efficient than using `Directory.GetFiles` since you  avoid iterating trough the entire file list.

Get a list of all matching files using [System.IO.DirectoryInfo.GetFiles()][1]


Also see SO Questions:

[Is there a wildcard expansion option for .net apps?][2]

[How do I check if a filename matches a wildcard pattern][3]

and many others...


  [1]: http://msdn.microsoft.com/en-us/library/ms143327.aspx
  [2]: https://stackoverflow.com/questions/381366/is-there-a-wildcard-expansion-option-for-net-apps
  [3]: https://stackoverflow.com/questions/652037/how-do-i-check-if-a-filename-matches-a-wildcard-pattern

Can anyone please tell me the difference between internal and external fragmentation while allocation of disk space for files?

Internal and external fragmentation

I have a web page which I have prevented the default action on all submit buttons, however I would like to re-enable default submit action on a button how can I do this?

I am currently preventing the default action using the following:

    $(&quot;form&quot;).bind(&quot;submit&quot;, function(e){
    e.preventDefault();
    });

I have successfully done this using the following: 

    $(document).ready(function(){
    $(&quot;form:not(&#39;#press&#39;)&quot;).bind(&quot;submit&quot;, function(e){
    e.preventDefault();
    });

But can I do this dynamically when the button is clicked?

How to reenable event.preventDefault?

I am using: 

    File.Exists(filepath)

What I would like to do is swop this out for a pattern, because the first part of the filename changes.

For example: the file could be

    01_peach.xml
    02_peach.xml
    03_peach.xml

How can I check if the file exists based on some kind of search pattern?

file exists by file name pattern

I am using:
<pre><code class="hljs language-arduino">File.Exists(filepath)
</code></pre>
What I would like to do is swop this out for a pattern, because the first part of the filename changes.
For example: the file could be
<pre><code class="hljs">01_peach.xml
02_peach.xml
03_peach.xml
</code></pre>
How can I check if the file exists based on some kind of search pattern?

How can i use the server.mappath method in a C# class library class ,which acts as my BusinessLayer for My ASP.NET WEbsite

Server.Mappath in C# classlibrary

I have a class whose constructor is defined as internal, which means I cannot instantiate it. While that may make sense, I would still like to do it once for debugging and research purposes.

Is it possible to do so with Reflection? I know I can access Private/Internal Members, but can I call an internal constructor?

Or, as the constructor does nothing important, can I use reflection to say &quot;Look, just give me an instance of the class without calling the constructor, I&#39;ll do it&#39;s work manually&quot;?

Performance and &quot;Stability&quot; is not an issue here, as it&#39;s not production code.

**Edit:** Just as clarification: Sadly, I don&#39;t control the other assembly and don&#39;t have it&#39;s source code, I merely try to understand how it works as it&#39;s documentation is next to non-existent, but I am supposed to interface with it.

Instancing a class with an internal constructor

How does the conversion to UTC from the standard `DateTime` format work?

More specifically, if I create a `DateTime` object in one time zone and then switch to another time zone and run `ToUniversalTime()` on it, how does it know the conversion was done correctly and that the time is still accurately represented?

How does DateTime.ToUniversalTime() work?

In ASP.NET C# I have a struct:

    public struct Data
    {
        public int item1;
        public int item2;
        public int category_id;
        public string category_name;
    }

and I have a List of those.  I want to select `category_id` and `category_name`, running a `DISTINCT` and finally an `ORDERBY` on `category_name`.

Here&#39;s what I have now:

    List&lt;Data&gt; listObject = getData();
    string[] catNames = listObject
                        .Select(i=&gt; i.category_name)
                        .Distinct()
                        .OrderByDescending(s =&gt; s)
                        .ToArray();

This obviously just gets the category name.  My question is, how do I get multiple fields, and what data structure will I store this in (not a `string[]`)?

EDIT

Using a list of structs is not set in stone.  If it would be advisable to change my backing data structure to make selects easier (I&#39;ll be writing a lot of these) then I&#39;d gladly take recommendations.

Select Multiple Fields from List in Linq

I&#39;m generating a receipt and am using the Graphics object to call the DrawString method to print out the required text.

    graphics.DrawString(string, font, brush, widthOfPage / 2F, yPoint, stringformat);

This works fine for what I needed it to do. I always knew what I was printing out, so I could manually trim any strings so it would fit properly on 80mm receipt paper. Then I had to add an extra bit of functionality that would make this more flexible. The user could pass in strings that would be added to the bottom.

Since I didn&#39;t know what they were going to put, I just created my own word wrap function that takes in a number of characters to wrap at and the string itself. In order to find out the number of characters, I was doing something like this:

    float width = document.DefaultPageSettings.PrintableArea.Width;
    int max = (int)(width / graphics.MeasureString(&quot;a&quot;, font).Width);

Now the width is returning me 283, which in mm is about 72, which makes sense when you account for margins on 80mm paper.

But the MeasureString method is returning 10.5 on a Courier New 8pt font. So instead of getting around what I expected to be 36 - 40, I&#39;m getting 26, resulting in 2 lines of text being turned into 3-4.

The units for PrintableArea.Width are 1/100th of an inch, and the PageUnit for the graphics object is Display (which says is typically 1/100th of an inch for printers). So why am I only getting 26 back?

Why is Graphics.MeasureString() returning a higher than expected number?

Whenever a user reports an error such as 
&gt; **System.Runtime.InteropServices.SEHException** - External component has thrown an exception?

is there anything that I as a programmer can do to determine the cause? 


Scenario : One user (using a program my company wrote) has reported this error. 
This may or may not have been a one off error. They mentioned that in the last month, the computer has twice &#39;stopped working&#39;. I have learnt from experience, not to take this description too literally, as it usually means that someone relating to the computer is not working as expected. They were unable to give me more details and I could not find any logged errors. Hence it may or may not have been this error.

From the stack-trace, the actual error was when constructing a class which does not directly call any interop code, but perhaps complicated by the fact that the object may be part of a list that is databound to a DevExpress Grid.

The error was &#39;caught&#39; by an unhandled exception routine which normally will close down the program, but has an option to ignore and continue. If they opted to ignore the error, then the program continued working but the error re-occurred when this routine was next run. However it did not occur again after closing and restarting our application. 

The computer in question did not seem to be stressed out. It is running Vista Business, has 2GB of memory and according to Task Manager was only using about half of that with our application just about 200Mb. 

There is one other piece of information that may or may not be relevant. Another section of the same program uses a third party component which is effectively a dotnet wrapper around a native dll and this component does have a known issue where very occasionally, you get a 

&gt; Attempted to read or write protected memory. This is often an indication that other memory is corrupt 

The component makers say that this has been fixed in the latest version of their component which we are using in-house, but this has not been given to the customer yet.

Given that the consequences of the error are low (no work is lost and restarting the program and getting back to where they were only takes a minute at most) and given that the customer will shortly be getting a new version (with the updated third-party component), I can obviously cross my fingers and hope the error won&#39;t occur again. 

But is there anything more I can do?

How should you diagnose the error SEHException - External component has thrown an exception

I&#39;ve written my own custom data layer to persist to a specific file and I&#39;ve abstracted it with a custom DataContext pattern.

This is all based on the .NET 2.0 Framework (given constraints for the target server), so even though some of it might look like LINQ-to-SQL, its not! I&#39;ve just implemented a similar data pattern.


See example below for example of a situation that I cannot yet explain.

To get all instances of `Animal` - I do this and it works fine
    
    public static IEnumerable&lt;Animal&gt; GetAllAnimals() {
            AnimalDataContext dataContext = new AnimalDataContext();
                return dataContext.GetAllAnimals();
    }

And the implementation of the `GetAllAnimals()` method in the `AnimalDataContext` below

    public IEnumerable&lt;Animal&gt; GetAllAnimals() {
            foreach (var animalName in AnimalXmlReader.GetNames())
            {
                yield return GetAnimal(animalName);
            }
    }

The `AnimalDataContext` implements `IDisposable` because I&#39;ve got an `XmlTextReader` in there and I want to make sure it gets cleaned up quickly.  

Now if I wrap the first call inside a using statement like so

    public static IEnumerable&lt;Animal&gt; GetAllAnimals() {
            using(AnimalDataContext dataContext = new AnimalDataContext()) {
                return dataContext.GetAllAnimals();
            }
    }

and put a break-point at the first line of the `AnimalDataContext.GetAllAnimals()` method and another break-point at the first line in the `AnimalDataContext.Dispose()` method, and execute...

**the `Dispose()` method is called FIRST so that `AnimalXmlReader.GetNames()` gives *&quot;object reference not set to instance of object&quot;* exception because `AnimalXmlReader` has been set to `null` in the `Dispose()` ???**

Any ideas? I have a hunch that its related to `yield return` not being allowed to be called inside a try-catch block, which `using` effectively represents, once compiled... 



yield return statement inside a using() { } block Disposes before executing

One of our clients has an old WinForms application that contains forms with a lot of controls on them. Some of those controls have a deep hierarchy and that makes it to hard to select them in the designer.

I need to understand this hierarchy to make modifications to the application to correct some bugs. Is there a way to see this hierarchy clearly? For example, is there something available that is similar to what can be seen in an .aspx source file when you have a breadcrumb of where you are in the HTML hierarchy (HTML &gt; Body &gt; div &gt; etc.)? Or something more visual maybe?



Show control hierarchy in the WinForms designer

I have two DLL files that have the same namespace but they have different methods and types.
How can I reference both DLLs in my project and use their methods and types?

By the way, these two DLLs have some methods and types with the same name but different implementation and some unique methods and types.

two different DLL with same namespace

I have form which is opened using ShowDialog Method. In this form i have a Button called More.
If we click on More it should open another form and it should close the current form.

on More Button&#39;s Click event Handler i have written the following code

  

    MoreActions objUI = new MoreActions (); 
    objUI.ShowDialog();
    this.Close();

But what is happening is, it&#39;s not closing the first form. So, i modified this code to 

  

    MoreActions objUI = new MoreActions (); 
    objUI.Show();
    this.Close();

Here, The second form is getting displayed and within seconds both the forms getting closed.

Can anybody please help me to fix issue.  What i need to do is, If we click on More Button, it should open another form and close the first form.

Any kind of help will be really helpful to me.

How to open a new form from another form

I have this:

    List&lt;object&gt; nodes = new List&lt;object&gt;(); 
    
    nodes.Add(
    new {
    	Checked		= false,
    	depth		= 1,
    	id			= &quot;div_&quot; + d.Id
    });


... and I&#39;m wondering if I can then grab the &quot;Checked&quot; property of the anonymous object.  I&#39;m not sure if this is even possible.  Tried doing this:

`if (nodes.Any(n =&gt; n[&quot;Checked&quot;] == false))`  ... but it doesn&#39;t work.

Thanks




How to access property of anonymous type in C#?

How can one get word wrap functionality for a `Label` for text which goes out of bounds?


Word wrap for a label in Windows Forms

I have tried very hard but cannot find a solution on how to set session timeout value for in-process session for an ASP.Net web application.

I am using VSTS 2008 + .Net 3.5 + C#. Here is what I wrote by myself to set timeout to be 1 minute, is it correct?

I wrote under system.web section in the `web.config`

    &lt;sessionState timeout=&quot;1&quot; mode=&quot;InProc&quot; /&gt;


Content Type	Original Author	Original Content on Stackoverflow
Question	JL.	View Question on Stackoverflow
Solution 1 - C#	monkey_p	View Answer on Stackoverflow
Solution 2 - C#	Claudio Redi	View Answer on Stackoverflow
Solution 3 - C#	Mitch Wheat	View Answer on Stackoverflow

file exists by file name pattern

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

Solution 3 - C#

How to reenable event.preventDefault?

Internal and external fragmentation

Attributions