C# Winform 文本框默认提示信息

private string Notes = "提示文本";

private void textBox1_Leave(object sender, EventArgs e)

{

    //  退出失去焦点，重新显示

    if (string.IsNullOrEmpty(textBox1.Text))

    {

        textBox1.ForeColor = Color.DarkGray;

        this.textBox1.Text = Notes;

    }

}

 

private void textBox1_Enter(object sender, EventArgs e)

{

    //  进入获得焦点，清空

    if (textBox1.Text == Notes)

    {

        textBox1.ForeColor = Color.Black;

        this.textBox1.Text = "";

    }

}