在表单加载上使用进度条

Question

对不起,我的英语不好

我正在尝试在C#中设计一个Win Form,它将在加载时从数据库中获取一些数据

我想使用进度条显示阅读数据进度

我试过这个代码(以及其他许多代码)

protected override void OnLoad(EventArgs e)
{
    base.OnLoad(e);
    this.Show();

    progressBar1.Value = 10;
    int n;

    n = 50;//number of records in DB ,
    double progress = 0;
    double progstep = 25 / n;
    for (int i = 1; i <= n; i++)
    {
        //getting 
        if (progress <= 100)
            progressBar1.Value = (int)progress;
    }

    progressBar1.Value = 35;

    n = 100;//number of records in DB for another data reading from DB ,
    progress = 35;
    progstep = 65 / n;
    for (int i = 1; i <= n; i++)
    {
        //getting data from DB
        dataGridView1.Rows.Add(....);//Adding that data to a datagrid -- parametrs removed.
        progress += progress;
        if (progress <= 100)
            progressBar1.Value = (int)progress;
    }

}

但是,问题是,Form将等待,直到数据读取进度完成,我只能看到一个完整的进度条和所有加载的数据.

我该怎么做才能解决这个问题？

谢谢

Answer 1

由于这是winforms,我建议使用BackgroundWorker.

基本示例:

bgWorker.DoWork += new DoWorkEventHandler(bgWorker_DoWork);
bgWorker.ProgressChanged += new DoWorkEventHandler(bgWorker_ProgressChanged);
bgWorker.RunWorkerAsync(//pass in object to process)

然后开始:

private void bgWorker_DoWork(object sender, DoWorkEventArgs e)
{
     //Do all of your work here
     bgWorker.ReportProgress(); //percent done calculation  
}

然后,Progress change事件将触发安全地更新UI:

private void bgWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
     progressBar.Value = e.ProgressPercentage;
}