Query builder method is available in .NET Framework 4.0
To use control with it, use it like this:
ObjectQuery<Product> productQuery =
context.Products
.Where("it.StandardCost > @cost", new ObjectParameter("cost", Textbox1.Text));
You can see the detail @
http://msdn.microsoft.com/en-us/library/bb896238.aspx#Y626[
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