C# TextBox增加Padding屬性，或者TextBox垂直居中

偏执的太偏执、 2022-09-27 09:17 535阅读 0赞

public partial class PubTextBox : TextBox  
    \{  
        //设置Rect消息  
        private const int EM\_SETRECT = 179;  
        //获取Rect消息  
        private const int EM\_GETRECT = 178;  
        //粘贴消息  
        private const int WM\_PASTE = 0x0302;  
        public PubTextBox()  
        \{  
            InitializeComponent();               
        \}  
  
        protected override void OnResize(EventArgs e)  
        \{  
            base.OnResize(e);  
            SetTextDispLayout();  
        \}  
  
        protected override void OnTextAlignChanged(EventArgs e)  
        \{  
            base.OnTextAlignChanged(e);  
            SetTextDispLayout();  
        \}  
  
        protected override void OnKeyPress(KeyPressEventArgs e)  
        \{  
            //如果不允许回车 屏蔽回车 换行键值  
            if (!AllowReturn  
                && ((int)e.KeyChar == (int)Keys.Return || (int)e.KeyChar == (int)Keys.LineFeed))  
            \{  
                e.Handled = true;  
            \}  
            base.OnKeyPress(e);  
        \}  
  
        /// <summary>  
        /// 窗体处理消息主函数 处理粘贴及绘制消息  
        /// </summary>  
        /// <param name="m"></param>  
        protected override void WndProc(ref System.Windows.Forms.Message m)  
        \{  
            string str = "";  
            bool flag = false;  
            int i = 0;  
            if (m.Msg == 0x0204)  
                i++;  
            if (!AllowReturn  
                && m.Msg == WM\_PASTE  
                && System.Windows.Forms.Clipboard.ContainsText())  
            \{  
                str = System.Windows.Forms.Clipboard.GetText();  
                System.Windows.Forms.Clipboard.Clear();  
                string nstr = str.Replace(char.ConvertFromUtf32((int)Keys.Return), "").Replace(char.ConvertFromUtf32((int)Keys.LineFeed), "");  
                System.Windows.Forms.Clipboard.SetText(nstr);  
                if (str.Length > 0) flag = true;  
            \}  
  
  
            base.WndProc(ref m);  
            if (flag)  
            \{  
                flag = false;  
                System.Windows.Forms.Clipboard.SetText(str);  
                str = "";  
            \}             
        \}  
        \[DllImport("user32.dll", EntryPoint = "SendMessageA")\]  
        private static extern int SendMessage(IntPtr hwnd, int wMsg, IntPtr wParam, string lParam);  
  
        \[DllImport("user32.dll", EntryPoint = "SendMessageA")\]  
        private static extern int SendMessage(IntPtr hwnd, int wMsg, IntPtr wParam, ref Rectangle lParam);  
  
        /// <summary>  
        /// 尺寸变化时重新设置字体的显示位置居中  
        /// </summary>  
        /// <param name="e"></param>  
        protected override void OnSizeChanged(EventArgs e)  
        \{  
            base.OnSizeChanged(e);  
            SetTextDispLayout();  
        \}  
  
        /// <summary>  
        /// 设置文本显示布局位置  
        /// </summary>  
        public void SetTextDispLayout()  
        \{  
            if (Text == "")  
                return;  
            //當允許多行和禁止回車時，Paddin有效  
            if (this.Multiline && (!this.WordWrap))  
            \{  
                Rectangle rect = new Rectangle();  
                SendMessage(this.Handle, EM\_GETRECT, (IntPtr)0, ref rect);  
                //SizeF size = CreateGraphics().MeasureString(Text, Font);//垂直居中 計算文本高度  
                //rect.Y = (int)(Height - size.Height) / 2 + TextPadding.Top;  
                rect.Y = TextPadding.Top;  
                rect.X = TextPadding.Left;  
                rect.Height = Height;  
                rect.Width = Width - TextPadding.Right - TextPadding.Left;  
                SendMessage(this.Handle, EM\_SETRECT, IntPtr.Zero, ref rect);  
            \}  
        \}      
  
        /// <summary>  
        /// 是否允许有回车  
        /// </summary>  
        \[CategoryAttribute("設定"), DisplayName("允許回車"), DescriptionAttribute("配合內邊使用")\]  
        public bool AllowReturn \{ get; set; \}  
  
        protected override void OnTextChanged(EventArgs e)  
        \{  
            base.OnTextChanged(e);  
  
            SetTextDispLayout();  
        \}  
  
        private Padding \_textpadding=new Padding(1);  
        /// <summary>  
        /// Text Padding值  當允許多行和禁止回車時，Paddin有效  
        /// </summary>  
        \[CategoryAttribute("設定"), DisplayName("內邊距"), DescriptionAttribute(" 當允許多行和禁止回車時，Paddin有效")\]

public Padding TextPadding \{ get \{ return \_textpadding; \} set \{ \_textpadding = value; SetTextDispLayout(); \} \}

![Center][]

參考：http://www.cnblogs.com/jason\_chen/p/6291295.html

[Center]: /images/20220708/70a13cd243634a5c8853181c1837ba98.png