Try putting the code in the Form&#39;s Shown event:

    private void myForm_Shown(object sender, EventArgs e)
    {
      txtLogEntries.SelectionStart = txtLogEntries.Text.Length;
      txtLogEntries.ScrollToCaret();
    }

While the [`Load`][1] event (occurs *before* the Form is shown) is processed, there is no form to display yet, and thus no visual state has been established. Scrolling a non-visible control therefore very likely doesn&#39;t do anything because—hey, there is nothing to scroll as a scrolling viewport is just a view on the control but not part of its state.

You may have more success with moving the scrolling part into the [`Shown`][2] event (occurs *after* the form is first shown) of the form


  [1]: http://msdn.microsoft.com/en-us/library/system.windows.forms.form.load.aspx
  [2]: http://msdn.microsoft.com/en-us/library/system.windows.forms.form.shown.aspx

Is there a good library for functional programming in Java?

I&#39;m looking for stuff like [Predicate][1] and [List.Find()][2] (as a static method). Not complicated to implement, but it would be nice to find a reusable library here.


  [1]: http://msdn.microsoft.com/en-us/library/bfcke1bz.aspx
  [2]: http://msdn.microsoft.com/en-us/library/x0b5b5bc.aspx

Functional Programming in Java

Here is the case:
I want to find the elements which match the regex...

&gt; targetText = &quot;SomeT1extSomeT2extSomeT3extSomeT4extSomeT5extSomeT6ext&quot;

and I use the regex in javascript like this

    reg = new RegExp(/e(.*?)e/g);   
    var result = reg.exec(targetText);

and I only get the first one, but not the follow....
I can get the T1 only, but not T2, T3 ... ...

How to loop all the elements that match the regex?

I have a TextBox on a C# Forms Application. I populate the TextBox with information on the Load event of the form. I then call the following:

    this.txtLogEntries.SelectionStart = txtLogEntries.Text.Length;
    this.txtLogEntries.ScrollToCaret();

However the TextBox does not scroll to the bottom ?

This only applies to the Load event though. I also update this TextBox from other parts of the application once it&#39;s running, and as soon as one of these events update&#39;s the TextBox, it is scrolled to the bottom.

So, how can I get it to scroll to the bottom when pre populating the TextBox in the Form Load event?


Scroll to bottom of C# TextBox

I have a TextBox on a C# Forms Application. I populate the TextBox with information on the Load event of the form. I then call the following:
<pre><code class="hljs language-ini">this.txtLogEntries.SelectionStart = txtLogEntries.Text.Length;
this.txtLogEntries.ScrollToCaret();
</code></pre>
However the TextBox does not scroll to the bottom ?
This only applies to the Load event though. I also update this TextBox from other parts of the application once it's running, and as soon as one of these events update's the TextBox, it is scrolled to the bottom.
So, how can I get it to scroll to the bottom when pre populating the TextBox in the Form Load event?

I want to base64 encode data to put it in a URL and then decode it within my HttpHandler.

I have found that [Base64 Encoding](http://en.wikipedia.org/wiki/Base64) allows for a &#39;/&#39; character which will mess up my UriTemplate matching.  Then I found that there is a concept of a &quot;modified Base64 for URL&quot; from wikipedia:

A modified Base64 for URL variant exists, where no padding &#39;=&#39; will be used, and the &#39;+&#39; and &#39;/&#39; characters of standard Base64 are respectively replaced by &#39;-&#39; and &#39;_&#39;, so that using URL encoders/decoders is no longer necessary and has no impact on the length of the encoded value, leaving the same encoded form intact for use in relational databases, web forms, and object identifiers in general.

Using .NET I want to modify my current code from doing basic base64 encoding and decoding to using the &quot;modified base64 for URL&quot; method.  Has anyone done this?

To decode, I know it starts out with something like:

    string base64EncodedText = base64UrlEncodedText.Replace(&#39;-&#39;, &#39;+&#39;).Replace(&#39;_&#39;, &#39;/&#39;);

    // Append &#39;=&#39; char(s) if necessary - how best to do this?

    // My normal base64 decoding now uses encodedText

But, I need to potentially add one or two &#39;=&#39; chars to the end which looks a little more complex.

My encoding logic should be a little simpler:

    // Perform normal base64 encoding
    byte[] encodedBytes = Encoding.UTF8.GetBytes(unencodedText);
    string base64EncodedText = Convert.ToBase64String(encodedBytes);

    // Apply URL variant
    string base64UrlEncodedText = base64EncodedText.Replace(&quot;=&quot;, String.Empty).Replace(&#39;+&#39;, &#39;-&#39;).Replace(&#39;/&#39;, &#39;_&#39;);
    
I have seen the [Guid to Base64 for URL](https://stackoverflow.com/questions/1032376/guid-to-base64-for-url) StackOverflow entry, but that has a known length and therefore they can hardcode the number of equal signs needed at the end.

Code for decoding/encoding a modified base64 URL (in ASP.NET Framework)

Is there any way to get the xml encoding in the toString() Function?

**Example:**

    xml.Save(&quot;myfile.xml&quot;);

leads to

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot;?&gt;
    &lt;Cooperations&gt;
      &lt;Cooperation&gt;
        &lt;CooperationId&gt;xxx&lt;/CooperationId&gt;
        &lt;CooperationName&gt;Allianz Konzern&lt;/CooperationName&gt;
        &lt;LogicalCustomers&gt;

But 

    tb_output.Text = xml.toString();


leads to an output like this

    &lt;Cooperations&gt;
      &lt;Cooperation&gt;
        &lt;CooperationId&gt;xxx&lt;/CooperationId&gt;
        &lt;CooperationName&gt;Allianz Konzern&lt;/CooperationName&gt;
        &lt;LogicalCustomers&gt;
        ...

XDocument.ToString() drops XML Encoding Tag

I found in [MSDN&#39;s Linq samples][1] a neat method called Fold() that I want to use.  Their example:

    double[] doubles = { 1.7, 2.3, 1.9, 4.1, 2.9 }; 
    double product = 
         doubles.Fold((runningProduct, nextFactor) =&gt; runningProduct * nextFactor); 

Unfortunately, I can&#39;t get this to compile, either in their example or in my own code, and I can&#39;t find anywhere else in MSDN (like Enumerable or Array extension methods) that mention this method.  The error I get is a plain old &quot;don&#39;t know anything about that&quot; error:

    error CS1061: &#39;System.Array&#39; does not contain a definition for &#39;Fold&#39; and no 
    extension method &#39;Fold&#39; accepting a first argument of type &#39;System.Array&#39; could 
    be found (are you missing a using directive or an assembly reference?)

I&#39;m using other methods which I believe come from Linq (like Select() and Where()), and I&#39;m &quot;using System.Linq&quot;, so I think that&#39;s all OK.

Does this method really exist in C# 3.5, and if so, what am I doing wrong?


  [1]: http://msdn.microsoft.com/en-us/vcsharp/aa336747.aspx#foldSimple

Where is the &quot;Fold&quot; LINQ Extension Method?

Tried to run Run Code Analysis on a project here, and got a number of warnings that said something like this:

&gt;CA1002 : Microsoft.Design : Change &#39;List&lt;*SomeType*&gt;&#39; in &#39;*SomeClass.SomeProtectedOrPublicProperty*&#39; to use Collection&lt;T&gt;, ReadOnlyCollection&lt;T&gt; or KeyedCollection&lt;K,V&gt;

Why should I use `Collection&lt;T&gt;` instead of `List&lt;T&gt;`? When I look at the msdn documentation, they seem almost equal. After reading the error help for the warning, I found that 

&gt;System.Collections.Generic.List(T)_is a generic collection designed for performance not inheritance and, therefore, does not contain any virtual members.

But what does this really mean? And what should I be doing instead?

Should I keep using `List&lt;T&gt;` internally, and then in the properties return a `new Collection&lt;T&gt;(someList)` instead? Or should I just start using `Collection&lt;T&gt;` instead of `List&lt;T&gt;`?

C#: Difference between List&lt;T&gt; and Collection&lt;T&gt; (CA1002, Do not expose generic lists)

I&#39;m using `DataContractJsonSerializer`, which likes to output to a Stream.  I want to top-and-tail the outputs of the serializer so I was using a StreamWriter to alternately write in the extra bits I needed.

    var ser = new DataContractJsonSerializer(typeof (TValue));

    using (var stream = new MemoryStream())
    {   
        using (var sw = new StreamWriter(stream))
        {
            sw.Write(&quot;{&quot;);

            foreach (var kvp in keysAndValues)
            {
                sw.Write(&quot;&#39;{0}&#39;:&quot;, kvp.Key);
                ser.WriteObject(stream, kvp.Value);
            }
            
            sw.Write(&quot;}&quot;);
        }

        using (var streamReader = new StreamReader(stream))
        {
            return streamReader.ReadToEnd();
        }
    }

When I do this I get an `ArgumentException` &quot;Stream was not readable&quot;.

I&#39;m probably doing all sorts wrong here so all answers welcome.  Thanks.

Writing to then reading from a MemoryStream

GUIs, whether written in WinForms or XAML, seem to have the most widely differing naming conventions between projects I see. For a simple `TextBox` for a person&#39;s name, I&#39;ve seen various naming conventions:

    TextBox tbName      // Hungarian notation
    TextBox txtName     // Alternative Hungarian
    TextBox NameTextBox // Not even camelCase
    TextBox nameTextBox // Field after field with TextBox on the end
    TextBox TextBoxName // Suggested in an answer...
    TextBox textBoxName // Suggested in an answer...
    TextBox uxName      // Suggested in an answer...
    TextBox name        // Deceptive since you need name.Text to get the real value
    TextBox textBox1    // Default name, as bad as you can get

I abide by the StyleCop rules for all my .cs files normally, and see others do so as well, but the GUI tends to break these rules or vary wildly. I haven&#39;t seen any Microsoft guidelines that specifically refer to GUI elements instead of just normal variables, or even examples that would apply outside of a console application. 

&lt;b&gt;What are the best practices for naming elements in a GUI?&lt;/b&gt;

Best practices for C# GUI naming conventions?

I have tried to do it without success. 

**Is it possible ?**

How to change the color of winform DataGridview header?

How can I set the column width of a c# winforms `listview` control to auto. Something like width = -1 / -2 ?

C# ListView Column Width Auto

How can I easily duplicate a C#/VB Form in Visual Studio? If I copy &amp; paste in the Solution Explorer, it uses the same class internally and gets messed up. How do you do it? 

How to easily duplicate a Windows Form in Visual Studio?

In my .NET 2.0 application, I need to check if sufficient permissions exist to create and write to files to a directory. To this end, I have the following function that attempts to create a file and write a single byte to it, deleting itself afterwards to test that permissions do exist.

I figured the best way to check was to actually try and do it, catching any exceptions that occur. I&#39;m not particularly happy about the general Exception catch though, so is there a better or perhaps a more accepted way of doing this?


    private const string TEMP_FILE = &quot;\\tempFile.tmp&quot;;
    
    /// &lt;summary&gt;
    /// Checks the ability to create and write to a file in the supplied directory.
    /// &lt;/summary&gt;
    /// &lt;param name=&quot;directory&quot;&gt;String representing the directory path to check.&lt;/param&gt;
    /// &lt;returns&gt;True if successful; otherwise false.&lt;/returns&gt;
    private static bool CheckDirectoryAccess(string directory)
    {
        bool success = false;
        string fullPath = directory + TEMP_FILE;
    
        if (Directory.Exists(directory))
        {
            try
            {
                using (FileStream fs = new FileStream(fullPath, FileMode.CreateNew, 
                                                                FileAccess.Write))
                {
                    fs.WriteByte(0xff);
                }
    
                if (File.Exists(fullPath))
                {
                    File.Delete(fullPath);
                    success = true;
                }
            }
            catch (Exception)
            {
                success = false;
            }
        }

Checking for directory and file write permissions in .NET

I&#39;m looking to accept digits and the decimal point, but no sign.

I&#39;ve looked at samples using the NumericUpDown control for Windows Forms, and [this sample of a NumericUpDown custom control from Microsoft][1]. But so far it seems like NumericUpDown (supported by WPF or not) is not going to provide the functionality that I want. The way my application is designed, nobody in their right mind is going to want to mess with the arrows. They don&#39;t make any practical sense, in the context of my application.

So I&#39;m looking for a simple way to make a standard WPF TextBox accept only the characters that I want. Is this possible? Is it practical?

  [1]: http://msdn.microsoft.com/en-us/library/ms771573.aspx



How do I get a TextBox to only accept numeric input in WPF?

I&#39;m trying to use asp:

    &lt;asp:TextBox ID=&quot;txtInput&quot; runat=&quot;server&quot; TextMode=&quot;MultiLine&quot;&gt;&lt;/asp:TextBox&gt;
 I want a way to specify the `maxlength` property, but apparently there&#39;s no way possible for a `multiline textbox`. I&#39;ve been trying to use some JavaScript for the `onkeypress` event: 

    onkeypress=&quot;return textboxMultilineMaxNumber(this,maxlength)&quot;

    function textboxMultilineMaxNumber(txt, maxLen) {
        try {
            if (txt.value.length &gt; (maxLen - 1)) return false;
        } catch (e) { }
        return true;
    }
While working fine the problem with this JavaScript function is that after writing characters it doesn&#39;t allow you to delete and substitute any of them, that behavior is not desired.

Have you got any idea what could I possibly change in the above code to avoid that or any other ways to get round it?

Specifying maxlength for multiline textbox

How to set the focus on an `TextBox` element in WPF

I have this code:

    txtCompanyID.Focusable = true;
    txtCompanyID.Focus();

...but it is not working.

Any idea?

Set focus on textbox in WPF

I have a `TextBox` and a `Button` in my view.

Now I am checking a condition upon button click and if the condition turns out to be false, displaying the message to the user, and then I have to set the cursor to the `TextBox` control.

    if (companyref == null)
    {
        var cs = new Lipper.Nelson.AdminClient.Main.Views.ContactPanels.CompanyAssociation(); 

        MessageBox.Show(&quot;Company does not exist.&quot;, &quot;Error&quot;, MessageBoxButton.OK,
                        MessageBoxImage.Exclamation);

        cs.txtCompanyID.Focusable = true;

        System.Windows.Input.Keyboard.Focus(cs.txtCompanyID);
    }

The above code is in the ViewModel.

The `CompanyAssociation` is the view name.

But the cursor is not getting set in the `TextBox`.

The xaml is:


    &lt;igEditors:XamTextEditor Name=&quot;txtCompanyID&quot; 
                             KeyDown=&quot;xamTextEditorAllowOnlyNumeric_KeyDown&quot;
                             ValueChanged=&quot;txtCompanyID_ValueChanged&quot;
                             Text=&quot;{Binding Company.CompanyId,
                                            Mode=TwoWay,
                                            UpdateSourceTrigger=PropertyChanged}&quot;
                             Width=&quot;{Binding ActualWidth, ElementName=border}&quot;
                             Grid.Column=&quot;1&quot; Grid.Row=&quot;0&quot;
                             VerticalAlignment=&quot;Top&quot;
                             HorizontalAlignment=&quot;Stretch&quot;
                             Margin=&quot;0,5,0,0&quot;
                             IsEnabled=&quot;{Binding Path=IsEditable}&quot;/&gt;

    &lt;Button Template=&quot;{StaticResource buttonTemp1}&quot;
            Command=&quot;{Binding ContactCommand}&quot;
            CommandParameter=&quot;searchCompany&quot;
            Content=&quot;Search&quot;
            Width=&quot;80&quot;
            Grid.Row=&quot;0&quot; Grid.Column=&quot;2&quot;
            VerticalAlignment=&quot;Top&quot;
            Margin=&quot;0&quot;
            HorizontalAlignment=&quot;Left&quot;
            IsEnabled=&quot;{Binding Path=IsEditable}&quot;/&gt;

Set focus on TextBox in WPF from view model

I want to detect whenever a textbox&#39;s content has changed. I can use the keyup method, but that will also detect keystrokes which do not generate letters, like the arrow keys. I thought of two methods of doing this using the keyup event:

 1. Check explictly if the ascii code of the pressed key is a letter\backspace\delete
 2. Use closures to remember what was the text in the textbox before the key stroke and check whether this has changed.

Both look kinda cumbersome. 

 

Content Type	Original Author	Original Content on Stackoverflow
Question	SnAzBaZ	View Question on Stackoverflow
Solution 1 - C#	bernhof	View Answer on Stackoverflow
Solution 2 - C#	Joey	View Answer on Stackoverflow

Scroll to bottom of C# TextBox

C# Problem Overview

C# Solutions

Solution 1 - C#

Solution 2 - C#

How to loop all the elements that match the regex?

Functional Programming in Java

Attributions