C# winfrom提示框，点击则不显示，不点击则提示输入内容

时间 2019-11-29

标签 c# winfrom 提示点击显示输入内容栏目 C# 繁體版

原文原文链接

先看下效果图，初次进来是界面左边的效果，点击请输入帐号，清除内容，能够直接输入，右边图ide

如下代码是失去焦点的，必定要把控件的属性TabStop 改成false。否则是不行的。工具

   #region 失去焦点
        protected override bool ProcessTabKey(bool forward)
        {
            foreach (Control c in this.Controls) { if (c is TextBox) { c.TabStop = true; } } return base.ProcessTabKey(forward); } #endregion

水印类this

把水印类添加在项目中。直接调用方法便可ComLogin_Loadspa

 /// <summary>
  /// 基于.NET 2.0的TextBox工具类
  /// </summary>
  public static class TextBoxToolV2
  {
    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); /// <summary> /// 为TextBox设置水印文字 /// </summary> /// <param name="textBox">TextBox</param> /// <param name="watermark">水印文字</param> public static void SetWatermark(this TextBox 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); } }

  private void ComLogin_Load(object sender, EventArgs e)
       {
           this.WindowState = FormWindowState.Maximized;
           TextBoxToolV2.SetWatermark(txtUserID, "请输入帐号");
           TextBoxToolV2.SetWatermark(txtEntryPwd, "请输入密码");
                   
        }