//////////////////////////////////////////////////////

///

///功能：可以改变文本行距（行间距）的Label

///作者：emanlee

///用于：c# 2003,2005

///时间：2006-8-10

///

/////////////////////////////////////////////////////

using System;

using System.ComponentModel;

using System.Collections.Generic;

using System.Diagnostics;

using System.Text;

using System.Drawing;

namespace compass.Common

{

    public partial class myLabel : System.Windows.Forms.Label

    {

        int lineDistance = 5;//行间距

        public int LineDistance

        {

            get { return lineDistance; }

            set { lineDistance = value; }

        }

        public myLabel()

        {

            InitializeComponent();

        }

        public myLabel(IContainer container)

        {

            container.Add(this);

            InitializeComponent();

        }

        protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)

        {

            Graphics g = e.Graphics;

            String drawString = this.Text;

            Font drawFont = this.Font;

            SolidBrush drawBrush = new SolidBrush(this.ForeColor);

            SizeF textSize = g.MeasureString(this.Text, this.Font);//文本的矩形区域大小

            int lineCount = Convert.ToInt16(textSize.Width / this.Width) + 1;//计算行数

            this.Height = Convert.ToInt16((textSize.Height + lineDistance) * lineCount);//计算调整后的高度

            this.AutoSize = false;

            float x = 0.0F;

            float y = 0.0F;

            StringFormat drawFormat = new StringFormat();

            int step = 1;

            lineCount = drawString.Length;//行数不超过总字符数目

            for (int i = 0; i < lineCount; i++)

            {

                //计算每行容纳的字符数目

                int charCount;

                for (charCount = 0; charCount < drawString.Length; charCount++)

                {

                    string subN = drawString.Substring(0, charCount);

                    string subN1 = drawString.Substring(0, charCount + 1);

                    if (g.MeasureString(subN, this.Font).Width <= this.Width

                        && g.MeasureString(subN1, this.Font).Width > this.Width)

                    {

                        step = charCount;

                        break;

                    }

                }

                string subStr;

                if (charCount == drawString.Length)//最后一行文本

                {

                    subStr = drawString;

                    e.Graphics.DrawString(subStr, drawFont, drawBrush, x, Convert.ToInt16(textSize.Height * i) + i * LineDistance, drawFormat);

                    break;

                }

                else

                {

                    subStr = drawString.Substring(0, step);//当前行文本

                    drawString = drawString.Substring(step);//剩余文本

                    e.Graphics.DrawString(subStr, drawFont, drawBrush, x, Convert.ToInt16(textSize.Height * i) + i * LineDistance, drawFormat);

                }

            }

        }

    }

}