Question

我有一个名为导出Excel 的功能，它基本上将数据导出到Excel并保存。所以我需要显示一个启动画面，直到我的功能完成工作。我怎么能这样做。

已编辑：如何在显示以下对话框之前关闭我的请稍候屏幕

我的代码段：

//对于背景工作者：

public Form1()
    {
        InitializeComponent();

        backgroundWorker1.WorkerReportsProgress = true;
        backgroundWorker1.WorkerSupportsCancellation = true;
        _f2 = new Form2();
    }

 private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;

        //backgroundWorker1.DoWork += new DoWorkEventHandler(this.ExportInExcel);
    }

    private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        _f2.Hide();
    }

private void button1_Click(object sender, EventArgs e)
    {
        _f2.Show();
        backgroundWorker1.RunWorkerAsync();
     ExportInExcel(lstExcel, @"Z:\Desktop\myExcel.xls"); // i need to show the splash screen and 
     //at the same time i need to do the function .. and close the splash screen after it   
     //completes the job.
    }

  private void ExportInExcel(SortedDictionary<string, ExcelData> lstData, string excelPath)
    {
        //some codes for precessing the file to excel
        xlApp.Quit();
        //xlApp.Close(false);
        //xlApp.Quit();
        Process[] pro = Process.GetProcessesByName("excel");

        pro[0].Kill();
        pro[0].WaitForExit();



        releaseObject(xlWorkSheet);
        releaseObject(xlWorkBook);
        releaseObject(xlApp);
    }

Answer 1

基本 Windows应用程序在单线程上运行，通常称为UI线程。

您可以使用BackgroundWorker。它正在与GUI的单独线程上工作。

此对象旨在简单地在不同的thread上运行一个函数，然后在UI线程上调用一个事件。

可用的文章很少：Example Project ＆amp; Multithreading

Answer 2

我建议使用BackgroundWorker和ProgressBar的组合。由于您不知道将来是否可以增加处理，因此最好在单独的线程上执行此操作，以便在用户单击按钮后尝试与父窗体交互时它不会冻结。

您可以查看以下有关如何使用ProgressBar控件和BackgroundWorker的文章：

a）ProgressBar

b）BackgroundWorker

您可以在同一表单上添加进度条，也可以使用像用户控件这样的小弹出窗口来显示进度条和文本。可以从后台工作程序（BackgroundWorker.ProgressChanged事件）发送进度更新。因此，您将ExportInExcel分成块并将更新发送到主窗体，这将更新进度条（10％.... 20％.... 30％）。一旦最后一次处理结束，您可以隐藏用户的进度条。

编辑：已添加示例

//Create a background worker
    private System.ComponentModel.BackgroundWorker backgroundWorker1 = new System.ComponentModel.BackgroundWorker();

//Add event handler to the background worker in your main form_load event

// tell the background worker it can report progress
backgroundWorker1.WorkerReportsProgress = true;

// add our event handlers
backgroundWorker1.RunWorkerCompleted += new RunWorkerCompletedEventHandler(this.RunWorkerCompleted);
backgroundWorker1.ProgressChanged += new ProgressChangedEventHandler(this.ProgressChanged);

//This is the method to do background work. Can be in a separate class.
backgroundWorker1.DoWork += new DoWorkEventHandler(this.ExportInExcel);


//On button click tell the worker to start. It will call the event handler of DoWork() i.e. ExportInExcel
 backgroundWorker1.RunWorkerAsync();

//In ExportInExcel update the progress when some part of work finishes. Pay attention to the signature of the method. It should of type DoWorkEventHandler
public void ExportInExcel(object sender, EventArgs e)
{
    BackgroundWorker worker = sender as BackgroundWorker;
    //process first step
    worker.ReportProgress(10, "Setting up the query");
    //and so on

}

//Progress changed from the worker
  public void ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    //update progress bar
}

private void RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
    //Work complete. Hide progress bar etc.
}

如何在我的功能完成之前显示加载屏幕

2 个答案: