C# BackgroundWorker WPF在进度条方面遇到的困难
我正在开发一个WPF、C#应用程序,我必须读取一个非常大的CSV文件并写入数据库。这个过程需要很长时间,所以我想至少显示一个进度条,当它接近完成时,它的大小会增加 现在,我在顶部有以下代码:C# BackgroundWorker WPF在进度条方面遇到的困难,c#,wpf,progress-bar,backgroundworker,C#,Wpf,Progress Bar,Backgroundworker,我正在开发一个WPF、C#应用程序,我必须读取一个非常大的CSV文件并写入数据库。这个过程需要很长时间,所以我想至少显示一个进度条,当它接近完成时,它的大小会增加 现在,我在顶部有以下代码: private readonly BackgroundWorker worker = new BackgroundWorker(); 然后在循环中我有这样一个: worker.WorkerReportsProgress = true; worker.ReportProgress((100 * i) / 1
private readonly BackgroundWorker worker = new BackgroundWorker();
然后在循环中我有这样一个:
worker.WorkerReportsProgress = true;
worker.ReportProgress((100 * i) / 10000);
我有一个像这样的私人潜水艇:
private void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
prgBar.Value = Math.Min(e.ProgressPercentage, 100);
}
但我并没有看到进度条更新或任何事情发生,程序仍然挂起。我做错什么了吗
更新:在这里尝试了MSDN指南,但不知何故,我没能让它与该示例一起工作。我当然调整了循环部分。呵呵。它仍然处于空闲状态,没有任何更新。见鬼,我想做的就是得到一个小计数器,每次读取和添加一行时,计数器都会增加
更新代码:
private BackgroundWorker bw = new BackgroundWorker();
public Process()
{
bw.WorkerReportsProgress = true;
bw.WorkerSupportsCancellation = true;
bw.DoWork += new DoWorkEventHandler(bw_DoWork);
bw.ProgressChanged += new ProgressChangedEventHandler(bw_ProgressChanged);
bw.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bw_RunWorkerCompleted);
}
private void bw_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker worker = sender as BackgroundWorker;
// Perform a time consuming operation and report progress.
int d = 0;
Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog();
// Set filter for file extension and default file extension
dlg.DefaultExt = ".csv";
dlg.Filter = "CSV File (*.csv)|*.csv";
dlg.Title = "file";
// Display OpenFileDialog by calling ShowDialog method
Nullable<bool> result = dlg.ShowDialog();
if (result == true)
{
// Open document
string filename = dlg.FileName;
List<String[]> fileContent = new List<string[]>();
using (FileStream reader = File.OpenRead(@filename)) // mind the encoding - UTF8
using (TextFieldParser parser = new TextFieldParser(reader))
{
using (SqlConnection conn = new SqlConnection(Classes.PublicVariables.Connection))
{
parser.Delimiters = new[] { "," };
parser.HasFieldsEnclosedInQuotes = true;
while (!parser.EndOfData)
{
string[] line = parser.ReadFields();
fileContent.Add(line);
SqlCommand comm = QUERYANDPARAMETERS
d += 1;
comm.ExecuteNonQuery();
worker.ReportProgress((d * 10));
}
}
}
}
private void bw_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
lblCount.Content = "Complete";
}
private void bw_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
this.lblCount.Content = (e.ProgressPercentage.ToString() + "%");
}
其他信息:对象引用未设置为对象的实例
更新3
开始工作了!我所需要的只是与上面相同的代码,但是:
if (bw.IsBusy != true)
{
bw.RunWorkerAsync();
}
else
{
bw_DoWork(null, null);
}
在按钮按下的事件处理程序中。这不会按原样编译,但应该让您从正确的方向开始:
private readonly BackgroundWorker worker
= new BackgroundWorker { WorkerReportsProgress = true };
public MainWindow()
{
InitializeComponent();
worker.DoWork += worker_DoWork;
worker.ProgressChanged += worker_ProgressChanged;
}
private void worker_DoWork(object sender, DoWorkEventArgs doWorkEventArgs)
{
// Do some long process, break it up into a loop so you can periodically
// call worker.ReportProgress()
worker.ReportProgress(i); // Pass back some meaningful value
}
private void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
prgBar.Value = Math.Min(e.ProgressPercentage, 100);
}
变量是否为
i
int?如果是,则(100*i)/10000
的值将返回0,而i<100。ReportProgress方法的参数应该是一个前值。您可以将其更改为worker.ReportProgress(i),试试看。从数学上讲,(100*i)/10000
与i/100
相同,我只是想在那里填充一些东西,然后改为9999:p。仍然没有。你在这里看过吗:?好的,让我看看我能不能让它与嫁妆一起工作。我第一次处理这个问题,如果你的后台工作人员很忙,你为什么打电话给bw_DoWork?这不符合目的,不是吗?我试试这个。谢谢格兰特
private readonly BackgroundWorker worker
= new BackgroundWorker { WorkerReportsProgress = true };
public MainWindow()
{
InitializeComponent();
worker.DoWork += worker_DoWork;
worker.ProgressChanged += worker_ProgressChanged;
}
private void worker_DoWork(object sender, DoWorkEventArgs doWorkEventArgs)
{
// Do some long process, break it up into a loop so you can periodically
// call worker.ReportProgress()
worker.ReportProgress(i); // Pass back some meaningful value
}
private void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
prgBar.Value = Math.Min(e.ProgressPercentage, 100);
}