textbox validation

Hi
I am completely new to c# .so i am just into basics.
just now i am beginning to work with windows forms

now i have to add a text box and a insert button
now when iam entering the text it should be inserted when the button is clicked.
now wht i need is that when teh text box is empty and when i clicked teh button , it should show a message saying that textbox is empty

I Think this is very smalll problem. But as ia m new, pls guide me to do it .

j o h n

This is the code you should write in the Click Event handler of your button

Code:

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private void button1_Click(object sender, System.EventArgs e)
{
        //Check the length of the text
        if (textBox1.Text.Length == 0 )
        {
                //show a message
                MessageBox.Show ("Textbox cannot be empty");
                //set focus back to textbox
                textBox1.Focus();
        }
        else
        {
                MessageBox.Show ("You entered : " + textBox1.Text);
        }
}

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