动态标签for循环中的文本
本文关键字:文本 循环 标签 for 动态 | 更新日期: 2023-09-27 18:07:54
我用c#做了一个简单的WF,试图动态地改变标签。
然而,当我运行这段代码时,没有可见的变化,直到代码运行之后,然后它改变为"处理9"0-8从未显示。是因为它在循环内吗?
private void button1_Click(object sender, EventArgs e)
{
for (int i = 0; i < 10; i++)
{
label9.Text = "Processing " + i.ToString();
Thread.Sleep(1000);
}
}
编辑:X-Tech的代码工作,但当我试图将其纳入我的代码,我得到以下线程问题。我试图动态地改变标签。当进度条摇摆时,循环中的文本:
系统类型的异常。在System.Windows.Forms.dll中发生了InvalidOperationException,但未在用户代码中处理其他信息:跨线程操作无效:控制'progressBar1'从创建它的线程以外的线程访问。如果有此异常的处理程序,则程序可以安全地继续
我不确定如何攻击这个,因为我不是非常熟悉Task.Factory.StartNew()和Invoke语句。
编辑2:改编代码:
Task.Factory.StartNew(() =>
{
for (int i = 0; i < lstFilesToZip.Items.Count; i++)
{
zipArray[i] = lstFilesToZip.Items[i].ToString();
// Report progress.
ExecuteSecure(() => label9.Text = "Processing :" + Path.GetFileNameWithoutExtension(lstFilesToZip.Items[i].ToString()));
ExecuteSecure(() => progressBar1.PerformStep());
string zipFileName = Path.GetFileName(zipArray[i]);
string newFolder = txtDestinationFolder.Text + "''" + Path.GetFileNameWithoutExtension(zipArray[i]);
//check to see if a directory with the file name for the zip file already exists, if not, it will create it
if (Directory.Exists(newFolder) == false)
{
DirectoryInfo newPath = Directory.CreateDirectory(newFolder);
if (lstCommonFiles.Items.Count > 0)
{
//copies each file in the common file list to each new folder created, the boolean indicates that it will overwrite existing files (true) or won't (false)
for (int k = 0; k < lstCommonFiles.Items.Count; k++)
{
File.Copy(lstCommonFiles.Items[k].ToString(), (newFolder + "''" + Path.GetFileName(commonArray[k])), true);
}
}
//adds the zip file into the folder as well
File.Copy(zipArray[i], (newFolder + "''" + zipFileName), true);
}
}
if (txtCommonFiles.Text.Length <= 0)
{
string result = "There are no common files selected, would you still like to proceed?";
DialogResult result1 = MessageBox.Show(result, "Common Files Missing", MessageBoxButtons.YesNo);
if (result1 == DialogResult.No)
{
return;
}
}
string[] dirs = Directory.GetDirectories(txtDestinationFolder.Text);
// Grabs the folders in the newly created directory
foreach (string dir in dirs)
lstDestinationFinal.Items.Add(dir);
//send sample file contents to preview window
string[] sampleFiles = Directory.GetFiles(lstDestinationFinal.Items[0].ToString());
//grabs the files
foreach (string zipFiles in sampleFiles)
lstSampleFile.Items.Add(zipFiles);
ExecuteSecure(() =>tabControl1.SelectedTab = tabPage2);
});
}
和添加的方法:
private void ExecuteSecure(Action action)
{
if (InvokeRequired)
{
Invoke(new MethodInvoker(() => action()));
}
else
{
action();
}
}
试试这个
Task.Factory.StartNew(() =>
{
for (int i = 0; i < 10; i++)
{
Invoke(new MethodInvoker(() => label9.Text = "Processing " + i.ToString()));
Thread.Sleep(1000);
}
});
编辑:Task.Factory.StartNew(() =>
{
for (int i = 0; i < 10; i++)
{
// Any GUI control which you want to use within thread,
// you need Invoke using GUI thread. I have declare a method below for this
//Now use this method as
ExecuteSecure(() => label9.Text = "Processing " + i);
ExecuteSecure(() => progressBar1.Value = i * 10);
//... other code etc.
Thread.Sleep(1000);
}
});
//---
private void ExecuteSecure(Action action)
{
if (InvokeRequired)
{
Invoke(new MethodInvoker(() => action()));
}
else
{
action();
}
}
如果你想让你的UI实时更新,使用BackgroundWorker,否则所有的工作都在UI线程上完成,并且它保持冻结状态,直到工作结束。
private void button1_Click(object sender, EventArgs e)
{
int limit = 10;
var bw = new BackgroundWorker();
bw.WorkerReportsProgress = true;
bw.DoWork += (s, ee) =>
{
for (int i = 0; i < limit; i++)
{
bw.ReportProgress(i);
Thread.Sleep(1000);
}
};
bw.ProgressChanged += (s, ee) => label9.Text = "Processing" + ee.ProgressPercentage.ToString();
bw.RunWorkerAsync();
}
不妨试试
private void button1_Click(object sender, EventArgs e)
{
for (int i = 0; i < 10; i++)
{
label9.Text = "Processing " + i.ToString();
Thread.Sleep(1000);
Form1.Refresh();
}
}
试试这个:
private void button1_Click(object sender, EventArgs e)
{
for (int i = 0; i < 10; i++)
{
label9.Text = "Processing " + i.ToString();
Application.DoEvents();
Thread.Sleep(1000);
}
}