stringformatflags

关注我的朋友们应该知道，我最近开始C# Winform自定义控件的学习，上一篇文章完成了一个最基本面板的控件，见链接C#学习随笔—自定义控件（面板）。

今天，我要分享的是自定义控件Label，在Winform自定义的Label中有一定局限性，举几个例子，比如，Label控件的换行就比较麻烦，Label文字中的对齐格式固定为居中对齐，Label没有边框，等等。那么自定义的Label控件，主要是解决上述问题。

读过我上一篇文章的朋友们应该知道，C#学习随笔—自定义控件（面板）里面的基本属性中包含了边框的颜色，宽度，虚实样式，边框的形状以及背景底色的调整（甚至是颜色的渐变）。因此在Label控件中只需要继承面板的这些属性即可实现这些功能，如下：

public partial class SimplyCtrlLabel : SimplyCtrlBa

因此，我们主要实现两点，一个是Label文字的对齐格式，如居中，靠左或者靠右，或者是边框想要随着文字多少的变化而变化。另外一个是Label Text的换行。

第一个关于Label文字的各种格式，我们需要对文本进行重绘，而且是在SimplyCtrlBa控件的基础上进行重绘，那么，需要怎么做呢？只需要增加重绘的调用事件即可，如下：

public SimplyCtrlLabel(){ InitializeComponent(); //Set Default Property. //Paint Text bad on Paint Event this.Paint += SimplyCtrlLabel_Paint;}private void SimplyCtrlLabel_Paint(object nder,PaintEventArgs e){ //文本重绘函数}

另外一个是Label文字的换行，我们需要在重绘函数中，对label的Text进行处理，识别到“ ”字符串，然后将其变为转义字符" "。

我这里先展示一下，我实现的控件的样子，如下所示：

Label控件不同属性的示例

直接上最后的代码：

using System;using System.Collections.Generic;using System.ComponentModel;using System.Drawing;using System.Data;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows.Forms;namespace MyLib_Simply{ public partial class SimplyCtrlLabel : SimplyCtrlBa { private bool _multiLineFlag = fal; [Description("Whether Label Text is multi-line, reprent change line in the LabelFontText"),Category("LabelUrDefined")] public bool MultiLineFlag { get { return _multiLineFlag; } t { _multiLineFlag = value; } } //边框高度自动适应 private bool _autoSuitHeight = fal; [Description("Whether Label Height is suitable for Text"),Category("LabelUrDefined")] public bool AutoSuitHeight { get { return _autoSuitHeight; } t { _autoSuitHeight = value; } } //边框宽度自动适应 private bool _autoSuitWidth = fal; [Description("Whether Label Width is suitable for Text"),Category("LabelUrDefined")] public bool AutoSuitWidth { get { return _autoSuitWidth; } t { _autoSuitWidth = value; } } private string _labelFontText = "Label"; [Description("Label Text"),Category("LabelUrDefined")] public string LabelFontText { get { return _labelFontText; } t { _labelFontText = value; } } //Text上下对齐方式 private StringAlignment _textHightAlignment = StringAlignment.Center; [Description("Label Text Height Alignment"),Category("LabelUrDefined")] public StringAlignment TextHightAlignment { get { return _textHightAlignment; } t { _textHightAlignment = value; } } //Text左右对齐方式 private StringAlignment _textWidthAlignment = StringAlignment.Center; [Description("Label Text Width Alignment"),Category("LabelUrDefined")] public StringAlignment TextWidthAlignment { get { return _textWidthAlignment; } t { _textWidthAlignment = value; } } public SimplyCtrlLabel() { InitializeComponent(); //Set Default Property. this.IsBorderShow = fal; this.IsRoundCorner = fal; this.IsKindsColor = fal; this.BackColor = SystemColors.Control; //Paint Text bad on Paint Event this.Paint += SimplyCtrlLabel_Paint; } private void SimplyCtrlLabel_Paint(object nder,PaintEventArgs e) { string label_text_modify = _labelFontText; if (_multiLineFlag) { //换行显示对Text进行处理。 label_text_modify = multi_line_text(_labelFontText); } StringFormat textformat = new StringFormat(); textformat.Alignment = _textWidthAlignment; textformat.LineAlignment = _textHightAlignment; if (this.RightToLeft == RightToLeft.Yes)//Check Layout is right to left or left to right { textformat.FormatFlags = StringFormatFlags.DirectionRightToLeft; } if ((_autoSuitHeight == fal) && (_autoSuitWidth == fal)) { } el { //测量String的宽度和高度，让边框自适应 int border_width, border_height; border_width = this.Width; border_height = this.Height; Graphics g = this.CreateGraphics(); g.PageUnit = GraphicsUnit.Pixel; g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; StringFormat sf = new StringFormat(); sf.FormatFlags = StringFormatFlags.MeasureTrailingSpaces; SizeF string_size = g.MeasureString(label_text_modify, this.Font, 1500, sf); if (_autoSuitHeight == true) { this.Height = Convert.ToInt32(string_size.Height)+2 ; } if (_autoSuitWidth == true) { this.Width = Convert.ToInt32(string_size.Width)+5 ; } } e.Graphics.DrawString(label_text_modify, this.Font, new SolidBrush(this.ForeColor), new RectangleF(1, 1, this.Width - 2, this.Height - 2), textformat); } //check label text and find out ' ',then convert to correct string private string multi_line_text(string text) { string text_modfiy=text; if (text != String.Empty) { string text_temp = text; text_modfiy = String.Empty; //@表示 为非转义字符 while (text_temp.IndexOf(@" ") >= 0) { text_modfiy += text_temp.Substring(0, text_temp.IndexOf(@" "))+" "; text_temp = text_temp.Substring(text_temp.IndexOf(@" ") + 2); } text_modfiy += text_temp; } return text_modfiy; } }}

今天Winform的C#自定义控件Label就分享到这里。希望可以帮到大家。