using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;


namespace HStation.RevitDev.RevitRelationMap.Utils
{
    /// <summary>
    /// TextBox 添加水印功能类
    /// </summary>
    public static class WaterRemark
    {
        private const int EM_SETCUEBANNER = 0x1501;
        [DllImport("user32.dll", CharSet = CharSet.Auto)]

        private static extern Int32 SendMessage
         (IntPtr hWnd, int msg, int wParam, [MarshalAs(UnmanagedType.LPWStr)] string lParam);

        public static void SetWatermark(this ComboBox comboBox, string watermark)
        {
            SendMessage(comboBox.Handle, EM_SETCUEBANNER, 0, watermark);
        }

        /// <summary>
        /// 为ToolStripTextBox设置水印文字
        /// </summary>ToolStripTextBox
        /// <param name="textBox">TextBox</param>
        /// <param name="watermark">水印文字</param>
        public static void SetWatermark(this ToolStripTextBox textBox, string watermark)
        {
            SendMessage(textBox.TextBox.Handle, EM_SETCUEBANNER, 0, watermark);
        }

        /// <summary>
        /// 为ToolStripTextBox设置水印文字
        /// </summary>ToolStripTextBox
        /// <param name="textBox">TextBox</param>
        /// <param name="watermark">水印文字</param>
        public static void SetWatermark(this RichTextBox textBox, string watermark)
        {
            SendMessage(textBox.Handle, EM_SETCUEBANNER, 0, watermark);
        }

        /// <summary>
        /// 清除水印文字
        /// </summary>
        /// <param name="textBox">TextBox</param>
        public static void ClearWatermark(this TextBox textBox)
        {
            SendMessage(textBox.Handle, EM_SETCUEBANNER, 0, string.Empty);
        }
    }
}