HanSolo

Handy javascript debugging tip

2012-04-25T08:38:09-12:00:00

In the project that I am working on, we have many forms that are loaded asynchronously via ajax. Some of these forms contain embedded javacript within the html. Sometimes it can be difficult to debug these scripts. One useful tip that I’ve learned is that you can add “debugger;” to the script where you want the browser to break. You are essentially setting a break point in the code itself by using the debugger statement. Whether you are using web inspector in chrome or firebug in firefox, this should tell the browser to break on that line of code. This will allow you to step through the code which has helped me immensely in debugging issues in dynamically loaded javascript scripts.

http://msdn.microsoft.com/en-us/library/0bwt76sk(v=vs.94).aspx

Open and close quotes

2012-04-13T07:20:06-12:00:00

Was troubleshooting issues today where our open and close quotes weren’t showing up correctly and found that it was because we were using the wrong character codes. We were using  but should have used “ Something to keep in mind for future reference.

http://www.dwheeler.com/essays/quotes-in-html.html

CKEditor and Javascript validation

2012-03-08T06:14:11-12:00:00

I have been working with CKEditor recently and ran into an issue where I noticed some strange random behavior with regards to validation. I noticed that sometimes the validation would pass or fail unexpectedly. It turns out that it was due to the fact that the CKEditor instance creates a separate element for user input and hides the original text area which the validation code validates. Since CKEditor doesn’t push the changes out to the text area until the control loses focus, if you click on the form submit button, the text area may or may not have been updated, so as a result, the validation may pass or fail unexpectedly.

The solution that I came up with was to add the following code to the form submit button before the form validation code. This ensures that the CKEditor content and the text area are always in sync when the validation runs.

//force each ckeditor instance on page to update their related text area elements so that we can perform validation on those elements

if (CKEDITOR != undefined) {

for (var instance in CKEDITOR.instances)

CKEDITOR.instances[instance].updateElement();

}

Hopes this helps someone that got stumped like I did.

Calling a .NET C# class from XSLT

2010-04-13T11:41:44-12:00:00

If you've ever worked with XSLT, you'd know that it's pretty limited when it comes to its programming capabilities. Try writing a for loop in XSLT and you'd know what I mean. XSLT is not designed to be a programming language so you should never put too much programming logic in your XSLT. That code can be a pain to write and maintain and so it should be avoided at all costs. Keep your xslt simple and put any complex logic that your xslt transformation requires in a class.

Here is how you can create a helper class and call that from your xslt. For example, this is my helper class:

 public class XsltHelper

        public string GetStringHash(string originalString)

            return originalString.GetHashCode().ToString();

And this is my xslt file(notice the namespace declaration that references the helper class):

<?xml version="1.0" encoding="UTF-8" ?>

<xsl:stylesheet  xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0" xmlns:ext="http://MyNamespace">

    <xsl:output method="text" indent="yes" omit-xml-declaration="yes"/>

    <xsl:template  match="/">The hash code of "<xsl:value-of select="stringList/string1" />" is "<xsl:value-of select="ext:GetStringHash(stringList/string1)" />".

    </xsl:template>

</xsl:stylesheet>

Here is how you can include the helper class as part of the transformation:

string xml = "<stringList><string1>test</string1></stringList>";

            XmlDocument xmlDocument = new XmlDocument();

            xmlDocument.LoadXml(xml);

            XslCompiledTransform xslCompiledTransform = new XslCompiledTransform();

            xslCompiledTransform.Load("XSLTFile1.xslt");

            XsltArgumentList xsltArgs = new XsltArgumentList();

            xsltArgs.AddExtensionObject("http://MyNamespace", Activator.CreateInstance(typeof(XsltHelper)));

            using (FileStream fileStream = new FileStream("TransformResults.txt", FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite))

                // transform the xml and output to the output file ...

                xslCompiledTransform.Transform(xmlDocument, xsltArgs, fileStream);

Writing to a file asynchronously

2009-10-15T13:48:45-12:00:00

Here is a code snippet for writing to a file asynchronously:

private void writeFileAsync(string text)

{

System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding();

byte[] buffer = encoding.GetBytes(text);

using (FileStream fs = new FileStream("temp.txt", FileMode.Append, FileAccess.Write, FileShare.ReadWrite, buffer.Length, FileOptions.Asynchronous))

{

IAsyncResult asyncResult = fs.BeginWrite(buffer, 0, buffer.Length, new AsyncCallback(EndWriteCallback), new State());

}

private void EndWriteCallback(IAsyncResult result)

{

}

DataGridView upper case textbox column

2009-09-15T00:30:37-12:00:00

It's a shame that the DataGridViewTextBoxColumn class doesn't allow you to set the casing so that you can restrict user input to all upper or lower case letters.

Fortunately, it's actually pretty easy to create a custom column class to do just that.

public class DataGridViewUpperCaseTextBoxColumn : DataGridViewTextBoxColumn

    public DataGridViewUpperCaseTextBoxColumn()

        : base()

        CellTemplate = new DataGridViewUpperCaseTextBoxCell();

public class DataGridViewUpperCaseTextBoxCell : DataGridViewTextBoxCell

    public DataGridViewUpperCaseTextBoxCell()

        : base()

    public override Type EditType

get

            return typeof(DataGridViewUpperCaseTextBoxEditingControl);

public class DataGridViewUpperCaseTextBoxEditingControl : DataGridViewTextBoxEditingControl

    public DataGridViewUpperCaseTextBoxEditingControl()

        : base()

        this.CharacterCasing = CharacterCasing.Upper;

Sweet fancy moses:)

Scrollable PictureBox control

2009-06-21T22:14:34-12:00:00

The PictureBox control in .NET does not have scroll bars, however, it is actually really easy to create a PictureBox control with scroll bars enabled. All you have to do is to drop a panel control onto a form, and set the AutoScroll property to true.

this.panel1.AutoScroll = true;

And drop a PictureBox control inside the panel and set the SizeMode to AutoSize.

this.pictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.AutoSize;

That's it.

Starting a background thread using the Threadpool

2009-05-09T13:42:00-12:00:00

Here is a quick and easy way of starting a background process using the Threadpool by way of an inline delegate.

ThreadPool.QueueUserWorkItem(new WaitCallback(

delegate(object stateInfo)

    saveToDB();

}));

Time enjoyed wasting is not wasted time

2009-04-29T21:18:54-12:00:00

Expect: 100-continue Header Problem

2009-04-28T23:13:56-12:00:00

Here is a way for you to disable the Expect: 100-continue Header:

string url = "http://www.myurl.com";

ServicePoint sp = ServicePointManager.FindServicePoint(new Uri(url));

sp.Expect100Continue = false;

I was getting a 500 http error when I tried to send a post to a Java web service through .Net using HttpWebRequest. Turning off this header did the trick. This will work even if you are using the WebClient class, which goes through HttpWebRequest under the covers. Hope this helps someone, this is a doozy of a problem to debug.