表单在后台工作程序中不显示为Dialog？ [英] Form does not displayed as Dialog inside backgroundworker?

问题描述

这是我的代码：

  //从Form1 
 private void backgroundWorkerResult_DoWork（object sender，DoWorkEventArgs e）
 {
 //在这里执行某些操作
 
 backgroundWorkerResult.ReportProgress （100）; 
 
 frmMessageBox frmMsgBox = new frmMessageBox（）; 
 frmMsgBox.ShowDialog（）; 
} 
  

即使我已经显示了 frmMsgBox 作为一个对话框我仍然可以点击 Form1 应该不是？如何解决这个问题？

解决方案

我创建了一个简单的代码示例，可以用来了解后台工作者的工作原理。将代码复制到测试表单并添加以下控件

1. 标签控件 - 将其命名为'lblStatus'


2. 进度条控制 - 应该命名progressBar1。


3. 添加名为btnStartAsyncOperation和btnCancel的两个按钮和链接他们的点击事件
。 >

基本上，您应该在 RunWorkerCompleted 事件

中显示结果

  public partial class Form1：Form 
 {
 BackgroundWorker backgroundWorker; 
 
 public Form1（）
 {
 InitializeComponent（）; 
 backgroundWorker = new BackgroundWorker {WorkerReportsProgress = true，WorkerSupportsCancellation = true}; 
 
 backgroundWorker.DoWork + = new DoWorkEventHandler（BackgroundWorker_DoWork）; 
 backgroundWorker.ProgressChanged + = new ProgressChangedEventHandler（BackgroundWorker_ProgressChanged）; 
 backgroundWorker.RunWorkerCompleted + = new RunWorkerCompletedEventHandler（BackgroundWorker_RunWorkerCompleted）; 
 
} 
 
 void BackgroundWorker_RunWorkerCompleted（object sender，RunWorkerCompletedEventArgs e）
 {
 if（e.Cancelled）
 lblStatus.Text =任务取消。 
 else if（e.Error！= null）
 lblStatus.Text =Error  - + e.Error.Message; 
 else 
 lblStatus.Text =任务完成...; 
 
 btnStartAsyncOperation.Enabled = true; 
 btnCancel.Enabled = false; 
} 
 
 void BackgroundWorker_ProgressChanged（object sender，ProgressChangedEventArgs e）
 {
 progressBar1.Value = e.ProgressPercentage; 
 lblStatus.Text =Processing ......+ progressBar1.Value.ToString（）+％; 
} 
 
 void BackgroundWorker_DoWork（object sender，DoWorkEventArgs e）
 {
 for（int i = 0; i< 100; i ++）
 { 
 System.Threading.Thread.Sleep（100）; 
 backgroundWorker.ReportProgress（i）; 
 if（backgroundWorker.CancellationPending）
 {
 e.Cancel = true; 
 backgroundWorker.ReportProgress（0）; 
 return; 
} 
} 
 backgroundWorker.ReportProgress（100）; 
} 
 
 private void btnStartAsyncOperation_Click（object sender，EventArgs e）
 {
 btnStartAsyncOperation.Enabled = false; 
 btnCancel.Enabled = true; 
 backgroundWorker.RunWorkerAsync（）; 
} 
 
 private void btnCancel_Click（object sender，EventArgs e）
 {
 if（backgroundWorker.IsBusy）
 {
 backgroundWorker.CancelAsync （）; 
} 
} 
} 
  

按照在OP中的评论

在DoWork事件中，按如下方式设置字符串

  e.Result =你的字符串; 
  

和RunWorkerCompleted事件

  string muResult = Convert.ToString（e.Result）; 
  

注意： e.Result是一个对象，所以你甚至可以设置具有多个属性的自定义类。

the Form does not displayed as Dialog inside backgroundworker?

Here is my code:

//From Form1
        private void backgroundWorkerResult_DoWork(object sender, DoWorkEventArgs e)
    {
        //do something here

        backgroundWorkerResult.ReportProgress(100);

        frmMessageBox frmMsgBox = new frmMessageBox();
        frmMsgBox.ShowDialog();
    }

Even though i already showed the frmMsgBox as a dialog i Can still click the Form1 that supposed to be not? how can fix this?

解决方案

I created a simple code sample that you can use to understand how the background worker works. Copy the code to a test form and add the following controls

1. Label Control - Name it 'lblStatus'
2. Progressbar Control - It should be named progressBar1.
3. Add 2 buttons named 'btnStartAsyncOperation' and 'btnCancel' and link their click events.

Basically you should display the results in the RunWorkerCompleted event

    public partial class Form1 : Form
    {
        BackgroundWorker backgroundWorker;

        public Form1()
        {
            InitializeComponent();
            backgroundWorker = new BackgroundWorker {WorkerReportsProgress = true, WorkerSupportsCancellation = true};

            backgroundWorker.DoWork += new DoWorkEventHandler(BackgroundWorker_DoWork);
            backgroundWorker.ProgressChanged += new ProgressChangedEventHandler(BackgroundWorker_ProgressChanged);
            backgroundWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(BackgroundWorker_RunWorkerCompleted);

        }

        void BackgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {
            if (e.Cancelled)
                lblStatus.Text = "Task Cancelled.";
            else if (e.Error != null)
                lblStatus.Text = "Error - " + e.Error.Message;
            else
                lblStatus.Text = "Task Completed...";

            btnStartAsyncOperation.Enabled = true;
            btnCancel.Enabled = false;
        }

        void BackgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            progressBar1.Value = e.ProgressPercentage;
            lblStatus.Text = "Processing......" + progressBar1.Value.ToString() + "%";
        }

        void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
        {
            for (int i = 0; i < 100; i++)
            {
                System.Threading.Thread.Sleep(100);
                backgroundWorker.ReportProgress(i);
                if (backgroundWorker.CancellationPending)
                {
                    e.Cancel = true;
                    backgroundWorker.ReportProgress(0);
                    return;
                }
            }
            backgroundWorker.ReportProgress(100);
        }

        private void btnStartAsyncOperation_Click(object sender, EventArgs e)
        {
            btnStartAsyncOperation.Enabled = false;
            btnCancel.Enabled = true;
            backgroundWorker.RunWorkerAsync();
        }

        private void btnCancel_Click(object sender, EventArgs e)
        {
            if (backgroundWorker.IsBusy)
            {
                backgroundWorker.CancelAsync();
            }
        }
    }

Edited as per comment by the OP

In the DoWork event, set your string as follows

 e.Result = "Your String";

and in the RunWorkerCompleted event

string muResult = Convert.ToString(e.Result);

NOTE: e.Result is an object so you can even set your custom classes with multiple properties in it.

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