Tuesday, December 29, 2009

Expression evaluation in Silverlight using eval

One of the previous posts in my general programming blog talks about evaluating the arithmetic expressions using the DataColumn and DataTables.The requirement was simple.You are given with an arithmetic expression say “(2+2)*3” as string. May be a user entered expression.You need to evaluate the given expression and show the answer.

In .Net it is easier.Use a DataColumn with the given expression and it will calculate the result for you.But when we come to Silverlight the things get harder.There is no concept of DataSet or DataTable in Silverlight.Rather the ADO.Net is not there.So what can we do?

One solution is to have a WCF server call which accepts the expression as string and use the ADO.Net DataColumn at server-side and return back the result.Obviously you can achieve that since the server is just a .Net application with ADO.Net support.But is that the better solution? I will say No because we have another alternative.

Its nothing but the famous eval function of javascript.I think all of you know how Silverlight can communicate with Javascript.If not please read this post about the same.

Here goes the solution.Get your expression.Pass it to the eval method of HtmlWindow.Use the return value properly.

private double Evaluate(string expression)
object obj = HtmlPage.Window.Eval(expression);
return Convert.ToDouble(obj);

Wednesday, December 16, 2009

Referring Silverlight 4 DLLs in WPF

Finally MSFT did it.Now we can use Silverlight assemblies in WPF without recompilation.In the older days we have to link the files to other solution and compile for Silverlight and WPF separately.Now that is over.Share your assemblies…

See what the CLR team says about this.

Tuesday, December 8, 2009

Finding Memory Leak in Silverlight

Finally one of my colleague opened the door to the Silverlight debugging using WinDbg and after a through google I was able to find out a great article by Delay regarding the same.


This blog tells about so many commands while debugging.So you may obviously in one question.What are the other commands? Here is the list of commands.

Enjoy debugging and stop the leaks in your application.