如何对动态创建的控件进行数据绑定？

Question

In the past, I've created data bindings like so:

textBoxPlatypusName.DataBindings.Add(new Binding("Text", PlatypusInfo, "PlatypusName"));

...but with dynamically-created controls, this is not possible (the compiler wouldn't be able to recognize "textBoxPlatypusName" at compile-time).

Trying this:

TextBox tb = (TextBox)this.Controls.Find("textBoxPlatypusName", true).First();
(TextBox)tb.DataBindings.Add(new Binding("Text", PlatypusInfo, "PlatypusName"));

...gives me, " Cannot convert type 'void' to 'System.Windows.Forms.TextBox' " and " Only assignment, call, increment, decrement, and new object expressions can be used as a statement "

Is there a way to accomplish this?

Answer 1

Remove the type casting. It is not required, since tb is already strongly typed as TextBox . The casting is wrong here anyway.

TextBox tb = (TextBox)this.Controls.Find("textBoxPlatypusName", true).First();
tb.DataBindings.Add(new Binding("Text", PlatypusInfo, "PlatypusName"));

If tb was typed as object or Control , for instance, and you needed to cast it to TextBox , you would need a second set of parentheses

((TextBox)control).SomePropertyOfTextBox = x;

Otherwise the casting is applied to the entire expression. In your case, C# wants to apply the casting to the result of the Add method, which is void and cannot be casted.