标签内容和进度条

Question

创建Windows窗体应用程序，并添加进度条显示的加载文件的进度，以及标签上方的进度条显示每个文件，但总和路径很长的路径，并显示在行，但我的宽格式对于小一些的路径不会出现所有的，我看到在堆栈溢出和谷歌不止一个解决方案，但确实为使汽车大小虚假，码头填不实用，并改变size.I想路径长度的方法动态变化。

Answer 1

为了让整个路径出现（例如换行），您需要将Label的Height设置为某个值，比如50。因此，它可能会像Label与50一个Height和300一个Width，然后是下方的ProgressBar。

而且，看来你的问题是，你在主线程上执行长时间运行的操作。这就是为什么Label不刷新。您需要使用BackgroundWorker。因此，添加一个类变量是：

private BackgroundWorker _worker = new BackgroundWorker(); 

然后在ctor做到这一点：

_worker.WorkerReportsProgress = true; 
_worker.DoWork += DoBackgroundWork; 
_worker.ProgressChanged += ReportProgress; 

，然后这些处理程序：

private void DoBackgroundWork(object sender, DoWorkEventArgs e) 
{ 
    // do the work you're doing in here -but add the below line when you want 
    // to update the text of your label 
    _worker.ReportProgress(1, "Your label text here"); 
} 

private void ReportProgress(object sender, ProgressChangedEventArgs e) 
{ 
    this.label.Text = e.UserState as string; 
} 

---

的最后一件事你可能要考虑，那就是切断字符串到关闭到您的标签的长度，而不是试图使其包装。下面是一组证明这种可能的解决方案的方法。

有一点要注意的是，截止程序利用了仓搜索，所以它不是难以置信准确。我的意思是什么？那么，假设您有一个长度为150个字符的字符串（如下例所示），并且第一次将它切成两半并测量字符串。如果宽度小于最大宽度（例如在Label的宽度），它只是将返回字符串。这很有效，但标签长度上可能存在空间并且可能会截断较少的字符。

为了使这个更准确，你将不得不作出更多的传球，以及国际海事组织，这只是没有足够重要的是要枚举的通行证。使用System.ComponentModel

public partial class Form1 : Form 
{ 
    string[] chars = new string[] 
    { 
     "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", 
     "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z" 
    }; 

    public Form1() 
    { 
     InitializeComponent(); 
    } 

    private void button1_Click(object sender, EventArgs e) 
    { 
     var filePath = BuildString(150); 
     var g = this.label1.CreateGraphics(); 
     var size = g.MeasureString(filePath, this.Font); 
     var oneCharacterLen = (size.Width/(float)filePath.Length); 
     if (size.Width > ((float)this.label1.Width - (oneCharacterLen * 3f))) 
     { 
      this.label1.Text = CutoffStringBinSearch(g, string.Format("{0}", filePath), 0, this.label1.Width); 
     } 
    } 

    private string CutoffStringBinSearch(Graphics g, string s, int startIndex, int maxWidth) 
    { 
     var midPoint = (s.Length - startIndex)/2; 
     var subString = string.Format("{0}...", s.Substring(startIndex, midPoint)); 

     var len = g.MeasureString(subString, this.Font); 
     if (len.Width > (float)maxWidth) { return CutoffStringBinSearch(g, s.Substring(startIndex, midPoint), 0, maxWidth); } 

     return subString; 
    } 

    private string BuildString(int len) 
    { 
     string[] s = new string[len]; 
     var random = new Random(0); 
     for (int i = 0; i < len; i++) 
     { 
      s[i] = chars[random.Next(0, chars.Length - 1)]; 
     } 
     return string.Join("", s); 
    } 
} 

Answer 2

using System; 

;使用System.Windows.Forms的 ;

命名空间BackgroundWorkerSimple { 公共部分Form1类：形式 { 公共Form1中（） { 的InitializeComponent（）; backgroundWorker1.WorkerReportsProgress = true; backgroundWorker1。WorkerSupportsCancellation = true; }

private void startAsyncButton_Click(object sender, EventArgs e) 
    { 
     if (backgroundWorker1.IsBusy != true) 
     { 
      // Start the asynchronous operation. 
      backgroundWorker1.RunWorkerAsync(); 
     } 
    } 

    private void cancelAsyncButton_Click(object sender, EventArgs e) 
    { 
     if (backgroundWorker1.WorkerSupportsCancellation == true) 
     { 
      // Cancel the asynchronous operation. 
      backgroundWorker1.CancelAsync(); 
     } 
    } 

    // This event handler is where the time-consuming work is done. 
    private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e) 
    { 
     BackgroundWorker worker = sender as BackgroundWorker; 

     for (int i = 1; i <= 10; i++) 
     { 
      if (worker.CancellationPending == true) 
      { 
       e.Cancel = true; 
       break; 
      } 
      else 
      { 
       // Perform a time consuming operation and report progress. 
       System.Threading.Thread.Sleep(500); 
       worker.ReportProgress(i * 10); 
      } 
     } 
    } 

    // This event handler updates the progress. 
    private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e) 
    { 
     resultLabel.Text = (e.ProgressPercentage.ToString() + "%"); 
    } 

    // This event handler deals with the results of the background operation. 
    private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) 
    { 
     if (e.Cancelled == true) 
     { 
      resultLabel.Text = "Canceled!"; 
     } 
     else if (e.Error != null) 
     { 
      resultLabel.Text = "Error: " + e.Error.Message; 
     } 
     else 
     { 
      resultLabel.Text = "Done!"; 
     } 
    } 
} 

}