Enter key press in C#

I tried this code:

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    if (Convert.ToInt32(e.KeyChar) == 13) 
    {
        MessageBox.Show(" Enter pressed ");
    }
}

and this:

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    if (e.KeyChar == Convert.ToChar(Keys.Enter))
    {
        MessageBox.Show(" Enter pressed ");
    }
}

and this:

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    if (e.KeyChar == Keys.Enter)
    {
        MessageBox.Show(" Enter pressed ");
    }
}

but they're not working...

When I write something and press Enter, it doesn't work. It only highlights my text.

Try this code,might work (Assuming windows form):

private void CheckEnter(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
    if (e.KeyChar == (char)13)
    {
        // Enter key pressed
    }
}

Register the event like this :

this.textBox1.KeyPress += new 
System.Windows.Forms.KeyPressEventHandler(CheckEnter);

You must try this in keydown event

here is the code for that :

private void textBox1_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.Key == Key.Enter)
        {
            MessageBox.Show("Enter pressed");
        }
    }

Update :

Also you can do this with keypress event.

Try This :

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
    {
        if (e.KeyChar == Convert.ToChar(Keys.Return))
        {
            MessageBox.Show("Key pressed");
        }
    }

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    if (e.KeyChar == (char)Keys.Enter)
    {
        MessageBox.Show("Enter Key Pressed");
    }
}

This allows you to choose the specific Key you want, without finding the char value of the key.