重写ProgressBar控件实现进度百分比显示 - (第十五讲)
视频讲解如下：
网盘下载，提取码：pt2b
https://pan.baidu.com/s/1C2ri-X89szdMtxfgc-feGg
这里给大家讲解一下如何重写ProgressBar控件实现进度百分比显示
演示效果如下：
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApp
{
public partial class MyProgressBar: ProgressBar
{
/// <summary>
/// 文本设置
/// </summary>
public Font TextFont { get; set; } = SystemFonts.DefaultFont;
/// <summary>
/// 渐变色开始
/// </summary>
public Color ColorStart { get; set; } = Color.FromArgb(204, 235, 255);
/// <summary>
/// 渐变色结束
/// </summary>
public Color ColorEnd { get; set; } = Color.FromArgb(0, 153, 255);
public MyProgressBar() : base()
{
this.SetStyle(ControlStyles.UserPaint, true);//自动绘制
this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);//减少闪烁
this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true);//减少闪烁
this.SetStyle(ControlStyles.DoubleBuffer, true);//减少闪烁
this.SetStyle(ControlStyles.ResizeRedraw, true);//重绘控件
this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);//减少闪烁
this.Paint += OnLabelPaint;
}
public void OnLabelPaint(object sender, PaintEventArgs e)
{
using (Graphics gr = this.CreateGraphics())
{
string str = this.Value.ToString() + "%";
// 设置渐变色
LinearGradientBrush brBG = new LinearGradientBrush(e.ClipRectangle,
ColorStart, ColorEnd, LinearGradientMode.Horizontal);
// 设置文字
float X = gr.MeasureString(str, TextFont).Width / 2.0F - 8;
float Y = this.Height / 2 - (gr.MeasureString(str, TextFont).Height / 2.0F) + 1; // 加1是向下微调，总感觉字偏上了
int W = e.ClipRectangle.Width * this.Value / this.Maximum;
int H = e.ClipRectangle.Height;
e.Graphics.FillRectangle(brBG, e.ClipRectangle.X, e.ClipRectangle.Y, W, H);
e.Graphics.DrawString(str, TextFont, Brushes.Black, new PointF(X, Y));
}
}
}
}
