C# 在使用委托运行后台工作时,如何处理控件启用/禁用选项?

C# 在使用委托运行后台工作时,如何处理控件启用/禁用选项?,c#,.net,delegates,C#,.net,Delegates,在按钮点击事件中,我有一个需要很长时间的查询。所以我在BackgroundWorker上运行它 private void btnGenerate_Click(object sender, EventArgs e) { btnGenerate.Enabled = false; BackgroundWorker worker = new BackgroundWorker(); worker.DoWork

在按钮点击事件中,我有一个需要很长时间的查询。所以我在BackgroundWorker上运行它

     private void btnGenerate_Click(object sender, EventArgs e)
        {
            btnGenerate.Enabled = false;
            BackgroundWorker worker = new BackgroundWorker();
            worker.DoWork += delegate (object s, DoWorkEventArgs args)
            {
                Data = DataLoader.GetData(Environment.UserName); // stored procedure execution 
                if (Data != null)
                {
                    GenerateExcel(Data);
                    GenerateSingleExcel(Data);
                } 
            };    
            worker.RunWorkerCompleted += delegate (object s, RunWorkerCompletedEventArgs args)
            {
                progressBar1.Visible = false;// ProgressBarStyle.Marquee 
                btnGenerate.Enabled = true;   
            };    
            worker.RunWorkerAsync();
}
我的问题是,我需要设置

btnGenerate.Enable=false

点击按钮。并在执行完成后启用

我在Runworker里试过了,已经完成了,但正在展示

'跨线程操作无效:从创建控件的线程以外的线程访问控件'btnGenerate'


任何建议都会有帮助。

您的主要问题是BackgroundWorker的事件是在工作线程上执行的,而不是在UI线程上执行的。但是UI元素只能从UI线程访问

为了解决这个问题,我建议使用async/await而不是BackgroundWorker:

如果DataLoader提供了异步GetDataAsync,那么您就不需要Task.Run了

如果由于任何原因无法实现异步,则RunWorkerCompleted处理程序应使用Invoke或:


我认为更好的方法是Data=wait Task.Run=>{var Data=…;…return Data;},以避免数据属性上的多线程问题。
// declare as async
private async void btnGenerate_Click(object sender, EventArgs e)
{
    btnGenerate.Enabled = false;
    Data = await Task.Run(() => {
                var data = DataLoader.GetData(Environment.UserName); // stored procedure execution 
                if (data != null)
                {
                    GenerateExcel(Data);
                    GenerateSingleExcel(Data);
                }
                return data; // as suggested by Vlad, don't set Data on this thread
            });    

    // this is now executed back on the UI thread
    progressBar1.Visible = false;// ProgressBarStyle.Marquee 
    btnGenerate.Enabled = true;   
}
worker.RunWorkerCompleted += OnRunWorkerCompleted;
//...
public void OnRunWorkerCompleted(object s, RunWorkerCompletedEventArgs args)
{
    if (InvokeRequired)
    {
        // not on the UI thread - use (Begin-)Invoke
        BeginInvoke(new RunWorkerCompletedEventHandler(OnRunWorkerCompleted), s, args);
        return;
    }

    // now we're on the UI thread
    progressBar1.Visible = false;// ProgressBarStyle.Marquee 
    btnGenerate.Enabled = true;   
}