如何在WPF C＃中显示进度条 [英] How to show Progress Bar in WPF C#

问题描述

Hello Friends，



我想在WPF窗口显示进度条。

我希望点击更新其值一个按钮。



我已经尝试了后台工作者，但它没有用。



请帮助实现简单的方法，通过它我可以更新UI表格上的值/文本。



我现在有以下代码 -

Hello Friends,

I want to show progress bar on WPF Window.
and I want to update its value by click on one Button.

I have tried background worker but it is not is of no use.

Please help to implement simple method by which I can update values/texts on UI Form.

I have below code till now -

 private void btn_Upload_Click(object sender, RoutedEventArgs e)
        {           
            Proc_Bar.Value = 0;
            BackgroundWorker worker = new BackgroundWorker();
            worker.WorkerReportsProgress = true;
            worker.DoWork += new DoWorkEventHandler(worker_DoWork);
            worker.RunWorkerAsync();

        }


  void worker_DoWork(object sender, DoWorkEventArgs e)
        {
            testProcBar();
            
        }


private void testProcBar()
        {
         

            Thread.Sleep(3000);
            Proc_Bar.Value = Proc_Bar.Value + 1;
            Thread.Sleep(3000);
            Proc_Bar.Value = Proc_Bar.Value + 1;
Thread.Sleep(3000);
            Proc_Bar.Value = Proc_Bar.Value + 1;
Thread.Sleep(3000);
            Proc_Bar.Value = Proc_Bar.Value + 1;
Thread.Sleep(3000);
            Proc_Bar.Value = Proc_Bar.Value + 1;
Thread.Sleep(3000);
            Proc_Bar.Value = Proc_Bar.Value + 1;
Thread.Sleep(3000);
            Proc_Bar.Value = Proc_Bar.Value + 1;


        }

请帮助。!!!

Please help.!!!

推荐答案

这是我的解决方案（取消支持）。按钮名为开始，进度条名为Progress1。

Here is a my solution (with cancelling support). Button is named "Start", Progress bar is named "Progress1".

private CancellationTokenSource _cancellation;

private async void Start_Click( object sender, RoutedEventArgs e )
{
    if ( _cancellation != null )
    {
        _cancellation.Cancel( false );
        _cancellation.Dispose();
    }
    _cancellation = new CancellationTokenSource();

    try
    {
        Debug.WriteLine(
          "Start_Click: My Thread id is {0}",
          Thread.CurrentThread.ManagedThreadId );

         // call it in another thread
         await Task.Run(
             () => AsyncUpdateProgressBar( _cancellation.Token ),
             _cancellation.Token )
           .ConfigureAwait( false );

         // call it in same thread
         //await AsyncUpdateProgressBar(_cancellation.Token);
     }
     catch ( TaskCanceledException )
     {
         // ignore
     }
 }

 private async Task AsyncUpdateProgressBar( CancellationToken token )
 {
     Debug.WriteLine(
       "AsyncUpdateProgressBar: My Thread id is {0}",
       Thread.CurrentThread.ManagedThreadId );

     for ( var i = 0; i <= 100 & !token.IsCancellationRequested; i++ )
     {
         // update value on dispatcher async
         // this is necessary, when calling this method from another thread
         // than the user interface thread!!!
         var tempLocal = i;
         await Dispatcher.InvokeAsync( () => Progress1.Value = tempLocal );

         // wait a little while
         await Task.Delay( 100, token );
     }

 }

创建类变量为

Create class variable as

private readonly SynchronizationContext context = null;

在构造函数中初始化：

initialize that in constructor :

this.context =  SynchronizationContext.Current;

现在每当更新UI线程我们如下：

Now whenever update the UI Thread us it like below :

this.context.Send(x => Proc_Bar.Value = Proc_Bar.Value + 1;, null);

这可能有所帮助，试试这个。

This might help, try this.

这篇关于如何在WPF C＃中显示进度条的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！