将控件ID传递给文本更改事件的自定义方法

Question

I would like to write a single method to handle the text changed event of several server controls on a webform. When the text changed event fires I need to pass the control ID to my method. In other words, when my method is called, I have to figure out which control caused the text changed event to fire. Is this possible? Normally I would use the command argument property but I don't think this is available for textbox and listbox controls. Any suggestions?

Answer 1

Use the Sender (first) parameter in the TextChanged function:

protected void TextBox1_TextChanged(object sender, EventArgs e)
{
        TextBox tb = sender as TextBox;

        if (tb != null)
        {
            string id = tb.ID;
        }
 }

Answer 2

your event handler has two parameters: object sender, eventargs e

The sender parameter is what you're looking for. Its actually a reference to the object which called the event handler, you just have to cast it to the correct type.

 TextBox fooBar = sender as TextBox;

then you can get the name if you desire:

 if(fooBar.Name == "someName") { ... }