在執(zhí)行耗時(shí)較長(zhǎng)的任務(wù)時(shí)，增加一個(gè)進(jìn)度條顯示任務(wù)的進(jìn)度，能夠給用戶一個(gè)很好的體驗(yàn)，如果沒(méi)有進(jìn)度條顯示進(jìn)度，用戶會(huì)誤以為程序運(yùn)行出錯(cuò)或死機(jī)了。那么在C#winform窗體應(yīng)用程序中如何設(shè)計(jì)一個(gè)進(jìn)度條呢，以下以一個(gè)簡(jiǎn)單的demo說(shuō)明過(guò)程。下面這個(gè)demo主要由三部分組成：主窗體、進(jìn)度顯示窗體、執(zhí)行任務(wù)的C#類。先來(lái)設(shè)計(jì)主窗體，主窗體只設(shè)置一個(gè)按鈕。注意：網(wǎng)上某些文章還在主窗體里設(shè)置了BackgroundWorker控件，我不建議直接使用BackgroundWorker控件，因?yàn)槭褂眠@個(gè)控件后，如果執(zhí)行任務(wù)過(guò)程中臨時(shí)取消任務(wù)，然后再次想要重啟任務(wù)時(shí)會(huì)出現(xiàn)錯(cuò)誤“此 BackgroundWorker 當(dāng)前正忙,無(wú)法同時(shí)運(yùn)行多個(gè)任務(wù)”。這是因?yàn)槭褂每丶r(shí)，BackgroundWorker對(duì)象成為一個(gè)固定的對(duì)象。在本demo中，直接在主窗體的按鈕點(diǎn)擊事件中用new方法創(chuàng)建BackgroundWorker對(duì)象，每次點(diǎn)擊按鈕都產(chǎn)生不同的BackgroundWorker對(duì)象。
using System;
using System.ComponentModel;
using System.Windows.Forms;
namespace Test
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public BackgroundWorker worker;
private void button1_Click(object sender, EventArgs e)
{
//創(chuàng)建一個(gè)Backgroundworker，設(shè)置其參數(shù)
this.worker = new BackgroundWorker();
worker.DoWork += new DoWorkEventHandler(backgroundwork); //執(zhí)行工作時(shí)，綁定對(duì)應(yīng)的方法
worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted); //工作完成時(shí)，綁定對(duì)應(yīng)的方法
worker.WorkerReportsProgress=true; //允許報(bào)告進(jìn)度
worker.WorkerSupportsCancellation=true; //支持中途取消
//開始執(zhí)行操作
worker.RunWorkerAsync();
ProcessForm form = new ProcessForm(worker);// 顯示進(jìn)度條窗體
form.ShowDialog(this);
form.Close();
}
private void backgroundwork(object sender, DoWorkEventArgs e)
{
DataOperate dataOperate = new DataOperate(); //執(zhí)行實(shí)際任務(wù)的類
dataOperate.operating(worker); //傳入worker，以便于報(bào)告進(jìn)度
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error != null)
{
MessageBox.Show(e.Error.Message);
}
else if (e.Cancelled)
{
this.worker.CancelAsync();
}
else
{
}
}
}
}
進(jìn)度條顯示窗體，由一個(gè)processbar控件和一個(gè)按鈕組成，界面如下：
using System;
using System.ComponentModel;
using System.Windows.Forms;
namespace Test
{
public partial class ProcessForm : Form
{
private BackgroundWorker backgroundWorker1;
public ProcessForm(BackgroundWorker backgroundWorker1)
{
InitializeComponent();
this.backgroundWorker1 = backgroundWorker1;
this.backgroundWorker1.ProgressChanged += new ProgressChangedEventHandler(backgroundWorker1_ProgressChanged);
this.backgroundWorker1.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted);
}
private void ProcessForm_Load(object sender, EventArgs e)
{
}
void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
this.Close();//執(zhí)行完之后，直接關(guān)閉頁(yè)面
}
void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
this.progressBar1.Value = e.ProgressPercentage;
}
private void button1_Click_1(object sender, EventArgs e)
{
this.backgroundWorker1.CancelAsync();
this.button1.Enabled = false;
this.Close();
}
}
}
最后，是執(zhí)行耗時(shí)任務(wù)的類DataOperate.cs，這里模擬了一個(gè)耗時(shí)10秒的任務(wù)，全部代碼如下：using System.ComponentModel;
using System.Threading;
namespace Test
{
internal class DataOperate
{
public void operating(BackgroundWorker worker)
{
for (int i = 0; i < 10; i++)
{
Thread.Sleep(1000);
worker.ReportProgress(i*100/10);
}
}
}
}
程序運(yùn)行后，點(diǎn)擊“開始”按鈕，就會(huì)彈出進(jìn)度條顯示進(jìn)度，點(diǎn)擊“取消”可取消任務(wù)，取消任務(wù)后可再次點(diǎn)擊“開始”再次執(zhí)行任務(wù)。
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該文章在 2025/1/7 11:42:10 編輯過(guò)
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