Kathy Kam : Code samples

WatermarkedTextBox for Silverlight 2 Beta 2

KathyKam — Tue, 24 Jun 2008 04:55:00 GMT

One breaking change you may have noticed between Silverlight 2 Beta 1 and Beta 2 is that WatermarkedTextBox is no longer available in the Silverlight SDK (System.Windows.Controls.Extended.dll).

We decided to remove the control because in a future version of Silverlight, we will be adding a “Watermark” property to TextBox. Given this upcoming change, it does not make sense to have "WatermarkedTextBox" as a separate control, so we decided to remove the control from Silverlight 2.

Because the update to TextBox will not happen until a future version of Silverlight feel free download and use the WatermarkedTextBox source code and unit test in the mean time. By downloading the source and unit tests you accept the license.

Here is an example on how to use it:

For more information on how to use this control, check out our Beta1 documentation in MSDN:

http://msdn.microsoft.com/en-us/library/system.windows.controls.watermarkedtextbox(VS.95).aspx

In additional to porting the source code & unit test for Beta 1, we also did the following:

Updated the template to use new features in the framework (i.e. VisualStateManager)
Bug fixing: When the control has focus, MouseOver state will no longer be active after moving the mouse away from the cotnrol
Bug fixing: Allow setting BorderBrush correctly

If you run into any problems, let me know! :)

<Editorial Note>
This is also a great example on how to use the new Visual State Manager for Silverlight 2 Beta 2!
Also a special "Thank you" to the WatermarkedTextBox dev Alex Bulankou for porting the source code, updating & fixing the bugs.
</Editorial Note>

Silverlight 2 Beta 2 has shipped!

KathyKam — Sat, 07 Jun 2008 07:52:00 GMT

Just a few hours ago, I was doing my talk based on Silverlight 2 Beta 2 bits and one of my attendee asked about when Beta 2 will be available. I am happy to annouce that it is now available!

Download the bits now on Silverlight.Net!

I have also updated my controls sample for Beta 2. I've made some significant changes and I hope you like it! :)

Silverlight Control Demo Sample
Uploaded on June 4
Created by: Microsoft

A sample of twenty-four Silverlight 2 controls that can be viewed live together with the source code used to drive the controls.

By clicking Download It you accept the license

I'm always interested to hear feedback, so remember to leave a comment and let me know what you think about the controls and the sample!

The links to my sample is broken on Silverlight.NET . I have contacted the owners of the page to see what's wrong. In the mean time, I have uploaded it on my WINISP account and set the links above to it. I'll update this blog once the links are fixed.

Links on Silverlight.Net is now fixed! Woohoo!

</Editorial Note>

Silverlight 2 Beta 1 Control Samples

KathyKam — Thu, 06 Mar 2008 00:54:50 GMT

My sample and its source is now live on http://silverlight.net! It show case a variety of controls we have built for the Silverlight 2 Beta 1. We have quite an good set of controls. It shouldn't surprise my readers to know that we have a DatePicker and a Calendar. :) And yes, I am the PM for those features. So for those of you who are sick of using my Silverlight 1.1 Calendar/DatePicker. Pick up the latest Silverlight 2 Beta 1!

Silverlight Control Demo Sample
Uploaded on March 5
Created by: Kathy Kam

A sample of twenty-four Silverlight 2 controls that can be viewed live together with the source code used to drive the controls.

Check out other samples here:

http://silverlight.net/community/gallerydetail.aspx?cat=5&sort=1#vid1080

Also, as mentioned by ScottGu this morning. You can download the source and unit tests to all the controls here:

http://www.microsoft.com/downloads/details.aspx?FamilyID=ea93dd89-3af2-4acb-9cf4-bfe01b3f02d4&displaylang=en

Love to hear what you think! I am excited to see applications people build with these controls. Tell me what you are building!

MonthCalendar and Datepicker control for Silverlight

KathyKam — Wed, 07 Nov 2007 04:00:00 GMT

In my spare time, I wrote a MonthCalendar and DatePicker control for Silverlight. It was just a side project for me to learn Silverlight.

My MonthCalendar and DatePicker can be downloaded here. The sample works with Silverlight 1.1 RC Alpha Refresh (Sept 2007) that can be downloaded here.

Please note that the code snippet is provided under the Microsoft Permissive Liceanse, and I provide it "as is" without warranty of any kind, either expressed or implied, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.

If you actually use it.. I'll be interested to know where and how! :)

TxRef update

KathyKam — Thu, 17 Nov 2005 02:49:00 GMT

If you opened up your CD from Krzysztof Cwalina and Brad Abram's new book Framework Design Guidelines. You will notice a nifty tool named TxRef. Unfortunately, the tool was written against "Whibey Beta", and some code needs to be updated for "Whidbey RTM".

Here is the updated code:

void WriteTypeConstraints(Type type)
    {
        foreach (Type t in type.GetGenericArguments())
        {
            bool writeComma = false;
            Type[] arr = t.GetGenericParameterConstraints();
            GenericParameterAttributes ga = t.GenericParameterAttributes & GenericParameterAttributes.SpecialConstraintMask;

            if ((arr.Length > 0) || (ga != GenericParameterAttributes.None))
            {
                Write(" where ");
                WriteTypeName(t);
                Write(":");
            }
            for (int i = 0; i < arr.Length; i++)
            {
                WriteTypeName(arr[i]);
                if (i < arr.Length - 1) Write(",");
            }

            if (arr.Length > 0) writeComma = true;
            if ((ga & GenericParameterAttributes.ReferenceTypeConstraint) != 0)
            {
                if (writeComma) Write(", ");
                Write("class");
                writeComma = true;
            }

            if ((ga & GenericParameterAttributes.NotNullableValueTypeConstraint) != 0)
            {
                if (writeComma) Write(", ");
                Write("struct");
                writeComma = true;
            }
            else if ((ga & GenericParameterAttributes.DefaultConstructorConstraint) != 0)
            {
                if (writeComma) Write(", ");
                Write("new()");
            }
        }
    }

Brad also talked about this particular breaking change in his blog here. I want to personally thank Andy for finding and reporting this error.

Augmenting to the Good For Nothing Compiler (Part 1 of 2)

KathyKam — Tue, 18 Oct 2005 04:49:00 GMT

A little while back, Joel posted the source to the Good For Nothing (GFN) Compiler and wondered what people can do with it. As a little side project, I added some features to the GFN Compiler which I will post in two parts.

Part 1: Making BCL calls from the GFN Compiler

Part 2: Making Function calls from the GFN Compiler

And without further ado.. here is part 1...

Part 1: Making BCL calls from the GFN Compiler

Here is the grammar modification I did to accomodate making BCL calls:

<func_stmt> := <scope><func_call>
<scope> := (<namespace>)? <scope>*
<namespace> := <ident>.
<func_call> := <ident> (<args>)

Additons to scanner.cs for class Scanner:

First, I need to scan the new objects for a function call into the tokens.

// Constants to represent arithmitic tokens. This could
// be alternatively written as an enum.
// ....
public static readonly object Comma = new object();
public static readonly object LeftBracket = new object(); // "("
public static readonly object RightBracket = new object(); // ")"

// Switch statment for character
// ....
else switch (ch)
{
case ',':
   input.Read();
   result.Add(Scanner.Comma);
   break;
case '(':
   input.Read();
   result.Add(Scanner.LeftBracket);
   break;
case ')':
   input.Read();
   result.Add(Scanner.RightBracket);
   break;
}

Additons to Ast.cs:

Then, I created a class to hold a function call.

public class FunctionCall : Stmt 
{ 
    public List<string> DotedScopes; 
    public string FunctionName; 
    public List<Expr> Args; 

    public FunctionCall() 
    { 
        DotedScopes = new List<string>(); 
        Args = new List<Expr>(); 
    } 
}

Additons to Parser.cs for class Paser:

I need to make additions to the Parser so that it can parse the function call into the the class I created in Ast.cs.

    private FunctionCall ParseFunc() 
    { 
        //Function calls 
        FunctionCall func = new FunctionCall(); 

        // function scope 
        while (this.index + 1 < this.tokens.Count 
            && this.tokens[this.index + 1] == Scanner.Dot) 
        { 
            func.DotedScopes.Add((string)this.tokens[this.index++]); 
            // Skips the dot 
            this.index++; 
        } 
        // Function Name 
        if (this.index == this.tokens.Count || 
            !(this.tokens[this.index] is string)) 
        { 
            throw new System.Exception("expected function name after scope"); 
        } 
        func.FunctionName = (string)this.tokens[this.index++]; 

        // Arguments 
        if (this.index == this.tokens.Count || 
            this.tokens[this.index] != Scanner.LeftBracket) 
        { 
            throw new System.Exception("expect open bracket after function name"); 
        } 
        this.index++;   // Skip Left Bracket 

        while ((this.tokens[this.index] != Scanner.RightBracket) 
            && (this.index < this.tokens.Count)) 
        { 
            func.Args.Add(this.ParseExpr()); 
            if (this.tokens[this.index] == Scanner.Comma) 
                this.index++; // Skip comma 
            else if (this.tokens[this.index] == Scanner.RightBracket) 
                break; 
            else 
                throw new System.Exception("unexpected character in arg list"); 
        } 

        if (this.index == this.tokens.Count || 
            this.tokens[this.index] != Scanner.RightBracket) 
        { 
            throw new System.Exception("expect close bracket after open bracket/args"); 
        } 
        this.index++;   // Skip RightBracket 

        return func; 
    } 
}

Additons to CodeGen.cs for class CodeGen

Now, the best part of writing a compiler... the actual code generation.

    private void CallFunction(FunctionCall func, out System.Type returnType) 
    { 
        System.Type[] typeArray = new System.Type[func.Args.Count]; 
        for (int i = 0; i < func.Args.Count; i++) 
        { 
            typeArray[i] = this.TypeOfExpr(func.Args[i]); 
            this.GenExpr(func.Args[i], typeof(object)); 
        } 
        Reflect.MethodInfo mi = null; 
        // BCL calls 
        if (func.DotedScopes.Count > 0) 
        { 
            Text.StringBuilder scope = new Text.StringBuilder(); 
            foreach (string str in func.DotedScopes) 
            { 
                scope.Append(str + "."); 
            } 
            // Remove the last dot 
            scope.Remove(scope.Length - 1, 1); 
            System.Type type = System.Type.GetType(scope.ToString()); 
            mi = type.GetMethod(func.FunctionName, typeArray); 
        } 
        else 
        // Local Function calls 
        { 
            if (!this.symbolTable.FunctionTable.ContainsKey(func.FunctionName)) 
            { 
                throw new System.Exception("function \"" + func.FunctionName + "\" not declared");     
            } 
            mi = this.symbolTable.FunctionTable[func.FunctionName]; 
        } 
        returnType = mi.ReturnType; 
        this.il.Emit(Emit.OpCodes.Call, mi); 
    }

Hello World - Reflection Style

KathyKam — Thu, 22 Sep 2005 00:48:00 GMT

My name is Kathy Kam and I am the newest addition to the Common Language Runtime (CLR) Program Management (PM) team. Like another PM on my team, JoelPob, I also grew up in the "Land Down Under". I left Sydney to pursue a degree in Computer Engineering and Mathematics at the University of Michigan - Ann Arbor. Upon graduation, I joined Microsoft as a developer for Microsoft Office Outlook. Four years later, after shipping Microsoft Office System 2003, a handful of Service Packs and working on Office 12 for two years, I decided to become a PM on the CLR team and here I am, writing my first post!

This blog will be a record of my insights to the .NET world. In the computing community, the first thing any developer writes is a "Hello World" program. Since this is a blog for all the computer geeks in us. Here it is, "Hello World" Reflection style:

using System;
using System.Reflection;

namespace HelloWorld
{
    class Program
    {
        static void Main(string[] args)
        {
            foreach (FieldInfo fi in typeof(HelloObj).GetFields())
                Console.Write(fi.Name + " ");
        }
    }

    class HelloObj
    {
        // My output
        public string Hello;
        public int World;
        public bool from;
        public int[] Kathy;
        public float Kam;
    }
}

The output will be:

> Hello World from Kathy Kam