在表单加载中使用进度条 [英] Using a Progress bar on Form Load

问题描述

对不起，我的英语不好

我正在尝试使用C#设计一个Win窗体，该窗体将在加载时从数据库中获取一些数据

I am trying to Design a Win Form in C# which will get some Data from a database while It's loading

我想使用进度条显示读取数据的进度

I want to use a progress bar to show reading data progress

我尝试了此代码(还有许多其他代码)

I tried this code (and also many others)

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，表单将等待，直到数据读取进度完成为止，我只能看到完整的进度条和所有加载的数据.

But , Problem is , Form will wait , until data reading progress be completed and I can see just a full progress bar and all data loaded.

我该怎么做才能解决此问题?

What Should I do too fix this?

谢谢

推荐答案

由于这是winforms，因此我建议使用

Since this is winforms, i'd recommend using a BackgroundWorker.

基本示例:

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

然后将开始:

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

然后将触发进度已更改"事件以安全地更新用户界面:

Then the Progress changed event would fire to update the UI safely:

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

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