Dynamic code in textbox ??

Question

Hi all,

I need something to know please help me.

Can I use the code in textbox??
For Ex:

I have a textbox (Name: code) to write the code and two other to enter values.

I write these in my first textbox :

Convert.ToDouble(value1.Text)+ Convert.ToDouble(value2.Text);

and when i click the button I want it to be calculated. and see the result as a string on a laber or whatever.

I read soo much articles but still I cant do it. Please help me. Thanks to all.