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进度条常用在加载，下载，导出一些比较耗时的地方，利用进度条能让用户看到实时进展，能有更好的用户体验……
直接开始
新建一个wpf项目，然后在主窗口添加一个按钮，用来控制进度的开始。加一个进度条控件progressbar。双击按钮，为按钮添加事件，代码直接循环模仿进度的进行……
代码语言：javascript复制private void button4_Click(object sender, RoutedEventArgs e){
for (int i = 0; i <= 100; i )
{
//当前进度，最大值默认100
progressBar1.Value = i;
Thread.Sleep(10);
}
}最简单的进度条已经完成，好的，这里运行程序执行，你会发现一个问题，点开始之后，界面直接卡住，回过神来，进度条已经满了，这和我们想像有点也不一样啊。你在ui线程里面执行了耗时的操作，就会让界面进入假死状态，这时候我们就要改进一下，使用多线程。
多线程开始
我们重新开启一个线程来模仿进度条进度，在按钮的点击事件下进行调用。好了，这次在点击按钮，我们可以看到进度条正常的显示进度情况了，不错，不错，是这种效果。
代码语言：javascript复制private void ProgressBegin() {
Thread thread = new Thread(new ThreadStart(() =>
{
for (int i = 0; i <= 100; i )
{
this.progressBar1.Dispatcher.BeginInvoke((ThreadStart)delegate{ this.progressBar1.Value = i; });
Thread.Sleep(100);
}
}));
thread.Start();
}新窗口来一个
这个写法是一样的，只不过在新窗口弄一个，用弹窗的方式来显示，有时候还是会用到的。新建一个wpf窗口，同样加入一个进度条控件，在主窗口的按钮点击事件中写入新窗口的创建和显示，在新窗口的构造函数中调用，进度条开始进度的方法。
代码语言：javascript复制//window1.xaml
<Window x:Class="progressbartest.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="217" Width="300"> <Grid>
<ProgressBar Height="24" HorizontalAlignment="Left" Margin="12,72,0,0" Name="progressBar1" VerticalAlignment="Top" Width="254" Foreground="#FF2EAFF1" />
</Grid></Window>
//window1.xaml.cs
using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Windows;using System.Windows.Controls;using System.Windows.Data;using System.Windows.Documents;using System.Windows.Input;using System.Windows.Media;using System.Windows.Media.Imaging;using System.Windows.Shapes;using System.Threading;namespace progressbartest
{
/// <summary>
/// Window1.xaml 的交互逻辑
/// </summary>
public partial class Window1 : Window
{
public Window1()
{
InitializeComponent();
ProgressBegin();
}
private void ProgressBegin()
{
Thread thread = new Thread(new ThreadStart(() =>
{
for (int i = 0; i <= 100; i )
{
this.progressBar1.Dispatcher.BeginInvoke((ThreadStart)delegate { this.progressBar1.Value = i; });
Thread.Sleep(100);
}
}));
thread.Start();
}
}
}BackgroundWork方式
BackgroundWorker类允许您在单独的线程上执行某个可能导致用户界面（UI）停止响应的耗时操作（比如文件下载数据库事务等），并且想要一个响应式的UI来反应当前耗时操作的进度。 那岂不是用来做进度条再合适不过了，可以利用单独线程来执行耗时操作，还能反应操作的进度。
当然，如果你要使用它提供的方法，必须要先设置一下它的某些属性，不然就没法使用，比如：要使用ReportProgress()（报告进度）的方法，先要设置WorkerReportsProgress=true。其他的设置，可以查官方文档哦。
代码语言：javascript复制private BackgroundWorker bgworker = new BackgroundWorker();
private void button3_Click(object sender, RoutedEventArgs e)
{
InitWork();
bgworker.RunWorkerAsync();
}
/// <summary>
/// 初始化bgwork
/// </summary>
private void InitWork()
{
bgworker.WorkerReportsProgress = true;
bgworker.DoWork = new DoWorkEventHandler(DoWork);
bgworker.ProgressChanged = new ProgressChangedEventHandler(BgworkChange);
}
private void DoWork(object sender, DoWorkEventArgs e)
{
for (int i = 0; i <= 100; i )
{
bgworker.ReportProgress(i);
Thread.Sleep(100);
}
}
/// <summary>
///改变进度条的值
/// </summary>
private void BgworkChange(object sender, ProgressChangedEventArgs e)
{
this.progressBar1.Value = e.ProgressPercentage;
}源代码
代码语言：javascript复制//mainwindow.xaml
<Window x:Class="progressbartest.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid>
<ProgressBar Height="23" HorizontalAlignment="Left" Margin="32,124,0,0" Name="progressBar1" VerticalAlignment="Top" Width="432" />
<Button Content="多线程开始" Height="23" HorizontalAlignment="Left" Margin="123,54,0,0" Name="button1" VerticalAlignment="Top" Width="75" Click="button1_Click" />
<Button Content="新窗口开始" Height="23" HorizontalAlignment="Left" Margin="219,54,0,0" Name="button2" VerticalAlignment="Top" Width="75" Click="button2_Click" />
<Button Content="BackgroundWorker方式" Height="23" HorizontalAlignment="Left" Margin="310,54,0,0" Name="button3" VerticalAlignment="Top" Width="154" Click="button3_Click" />
<Button Content="开始" Height="23" HorizontalAlignment="Left" Margin="32,54,0,0" Name="button4" VerticalAlignment="Top" Width="75" Click="button4_Click" />
</Grid>
</Window>
//mainwindow.xaml.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Threading;
using System.ComponentModel;
namespace progressbartest
{
/// <summary>
/// MainWindow.xaml 的交互逻辑
/// </summary>
public partial class MainWindow : Window
{
private BackgroundWorker bgworker = new BackgroundWorker();
public MainWindow()
{
InitializeComponent();
}
private void button1_Click(object sender, RoutedEventArgs e)
{
ProgressBegin();
}
private void ProgressBegin()
{
Thread thread = new Thread(new ThreadStart(() =>
{
for (int i = 0; i <= 100; i )
{
this.progressBar1.Dispatcher.BeginInvoke((ThreadStart)delegate{ this.progressBar1.Value = i; });
Thread.Sleep(100);
}
}));
thread.Start();
}
private void button2_Click(object sender, RoutedEventArgs e)
{
Window1 window = new Window1();
window.Show();
}
/// <summary>
/// 初始化bgwork
/// </summary>
private void InitWork()
{
bgworker.WorkerReportsProgress = true;
bgworker.DoWork = new DoWorkEventHandler(DoWork);
bgworker.ProgressChanged = new ProgressChangedEventHandler(BgworkChange);
}
private void DoWork(object sender, DoWorkEventArgs e)
{
for (int i = 0; i <= 100; i )
{
bgworker.ReportProgress(i);
Thread.Sleep(100);
}
}
/// <summary>
///改变进度条的值
/// </summary>
private void BgworkChange(object sender, ProgressChangedEventArgs e)
{
this.progressBar1.Value = e.ProgressPercentage;
}
private void button3_Click(object sender, RoutedEventArgs e)
{
InitWork();
bgworker.RunWorkerAsync();
}
private void button4_Click(object sender, RoutedEventArgs e)
{
for (int i = 0; i <= 100; i )
{
progressBar1.Value = i;
Thread.Sleep(10);
}
}
}
}
//window1.xaml
<Window x:Class="progressbartest.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="217" Width="300">
<Grid>
<ProgressBar Height="24" HorizontalAlignment="Left" Margin="12,72,0,0" Name="progressBar1" VerticalAlignment="Top" Width="254" Foreground="#FF2EAFF1" />
</Grid>
</Window>
//window1.xaml.cs
using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Windows;using System.Windows.Controls;using System.Windows.Data;using System.Windows.Documents;using System.Windows.Input;using System.Windows.Media;using System.Windows.Media.Imaging;using System.Windows.Shapes;using System.Threading;namespace progressbartest
{
/// <summary>
/// Window1.xaml 的交互逻辑
/// </summary>
public partial class Window1 : Window
{
public Window1()
{
InitializeComponent();
ProgressBegin();
}
private void ProgressBegin()
{
Thread thread = new Thread(new ThreadStart(() =>
{
for (int i = 0; i <= 100; i )
{
this.progressBar1.Dispatcher.BeginInvoke((ThreadStart)delegate { this.progressBar1.Value = i; });
Thread.Sleep(100);
}
}));
thread.Start();
}
}
}参考资料
BackgroundWorker使用总结 https://blog.csdn.net/coderookieguo/article/details/72723310
