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为了实现异步搜索C:\Program Files文件夹下包含“scyGroupBox”关键字的代码文件，我们可以使用C#中的委托和异步方法。以下是详细的实现步骤：

步骤1：定义委托类型

定义一个委托类型，指向耗时的文件搜索函数：

public delegate List
   
     AddListViewDelegate();
   

步骤2：实现耗时函数

编写一个函数，用于搜索文件，并返回包含指定关键字的文件列表：

public List
   
     LoadFileByName()
{
    string keyword = "scyGroupBox";
    string path = @"C:\Program Files\";
    DirectoryInfo directory = new DirectoryInfo(path);
    var files = directory.GetFiles("*.cs", SearchOption.AllDirectories)
                      .Where(p => p.Name.Contains(keyword))
                      .ToList();
    return files;
}
   

步骤3：定义异步操作

创建一个类，包含异步操作的逻辑：

public class AsyncFileSearch
{
    private readonly ListView _lsvName;
    private readonly List
   
     _myFiles;
    private readonly bool _addFlag;
    private readonly bool _deleteFlag;
    public AsyncFileSearch(ListView lsvName, List
    
      myFiles, bool addFlag, bool deleteFlag)
    {
        _lsvName = lsvName;
        _myFiles = myFiles;
        _addFlag = addFlag;
        _deleteFlag = deleteFlag;
    }
    public void InvokeListView()
    {
        AddListViewDelegate asyncAdd = new AddListViewDelegate(LoadFileByName);
        IAsyncResult iar = asyncAdd.BeginInvoke(new AsyncCallback(GetFileInfoResult), asyncAdd);
        AddNotification();
    }
    private void GetFileInfoResult(IAsyncResult iar)
    {
        AddListViewDelegate asyncAdd = (AddListViewDelegate)iar.AsyncState;
        List
     
       list = asyncAdd.EndInvoke(iar);
        LoadFileIntoForm(list);
    }
    private void LoadFileIntoForm(List
      
        fileList)
    {
        _myFiles = fileList;
        ClearListView();
        foreach (FileInfo file in fileList)
        {
            ListViewItem lvi = new ListViewItem
            {
                Text = Path.GetFileName(file.FullName),
                Tag = file.FullName
            };
            AddListViewCrossThreads(lvi, _addFlag);
        }
    }
    private void ClearListView()
    {
        _lsvName.Items.Clear();
    }
    private void AddNotification()
    {
        ListViewItem loadingItem = new ListViewItem
        {
            Text = "正在加载，请稍等……",
            Tag = 1
        };
        _lsvName.Items.Add(loadingItem);
    }
    private void AddListViewCrossThreads(ListViewItem lvi, int action)
    {
        if (_lsvName.InvokeRequired)
        {
            AddListViewCrossThreadDelegate del = new AddListViewCrossThreadDelegate(AddListViewCrossThreads);
            _lsvName.Invoke(del, lvi, action);
        }
        else
        {
            if (action == _addFlag)
            {
                _lsvName.Items.Add(lvi);
            }
            else if (action == _deleteFlag)
            {
                _lsvName.Items.Clear();
            }
        }
    }
}
      
     
    
   

步骤4：在主程序中使用异步操作

调用AsyncFileSearch类的方法：

AsyncFileSearch asyncFileSearch = new AsyncFileSearch(lsvName, fileList, addFlag, deleteFlag);
asyncFileSearch.InvokeListView();

步骤5：处理异常

在GetFileInfoResult方法中，处理可能的异常：

catch (Exception ex)
{
    MessageBox.Show("搜索失败：" + ex.Message);
}
finally
{
    asyncAdd?.Invoke(null, null);
}

步骤6：优化用户体验

在异步过程中，显示loading提示信息，避免用户等待：

asyncFileSearch.AddNotification();

完整代码示例

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading;
using System.Windows.Forms;
public class AsyncFileSearch
{
    private readonly ListView _lsvName;
    private readonly List
   
     _myFiles;
    private readonly bool _addFlag;
    private readonly bool _deleteFlag;
    public AsyncFileSearch(ListView lsvName, List
    
      myFiles, bool addFlag, bool deleteFlag)
    {
        _lsvName = lsvName;
        _myFiles = myFiles;
        _addFlag = addFlag;
        _deleteFlag = deleteFlag;
    }
    public void InvokeListView()
    {
        AddListViewDelegate asyncAdd = new AddListViewDelegate(LoadFileByName);
        IAsyncResult iar = asyncAdd.BeginInvoke(new AsyncCallback(GetFileInfoResult), asyncAdd);
        AddNotification();
    }
    private void GetFileInfoResult(IAsyncResult iar)
    {
        AddListViewDelegate asyncAdd = (AddListViewDelegate)iar.AsyncState;
        List
     
       list = asyncAdd.EndInvoke(iar);
        LoadFileIntoForm(list);
    }
    private void LoadFileIntoForm(List
      
        fileList)
    {
        _myFiles = fileList;
        ClearListView();
        foreach (FileInfo file in fileList)
        {
            ListViewItem lvi = new ListViewItem
            {
                Text = Path.GetFileName(file.FullName),
                Tag = file.FullName
            };
            AddListViewCrossThreads(lvi, _addFlag);
        }
    }
    private void ClearListView()
    {
        _lsvName.Items.Clear();
    }
    private void AddNotification()
    {
        ListViewItem loadingItem = new ListViewItem
        {
            Text = "正在加载，请稍等……",
            Tag = 1
        };
        _lsvName.Items.Add(loadingItem);
    }
    private void AddListViewCrossThreads(ListViewItem lvi, int action)
    {
        if (_lsvName.InvokeRequired)
        {
            AddListViewCrossThreadDelegate del = new AddListViewCrossThreadDelegate(AddListViewCrossThreads);
            _lsvName.Invoke(del, lvi, action);
        }
        else
        {
            if (action == _addFlag)
            {
                _lsvName.Items.Add(lvi);
            }
            else if (action == _deleteFlag)
            {
                _lsvName.Items.Clear();
            }
        }
    }
    private void LoadFileIntoForm(List
       
         fileList)
    {
        _myFiles = fileList;
        ClearListView();
        foreach (FileInfo file in fileList)
        {
            ListViewItem lvi = new ListViewItem
            {
                Text = Path.GetFileName(file.FullName),
                Tag = file.FullName
            };
            AddListViewCrossThreads(lvi, _addFlag);
        }
    }
    private void ClearListView()
    {
        _lsvName.Items.Clear();
    }
    public List
        
          LoadFileByName() { string keyword = "scyGroupBox"; string path = @"C:\Program Files\"; DirectoryInfo directory = new DirectoryInfo(path); var files = directory.GetFiles("*.cs", SearchOption.AllDirectories) .Where(p => p.Name.Contains(keyword)) .ToList(); return files; } }
        
       
      
     
    
   

使用示例

// 初始化列表视图
ListView lsvName = new ListView();
// 初始化文件列表
List
   
     fileList = new List
    
     ();
// 调用异步搜索
AsyncFileSearch asyncFileSearch = new AsyncFileSearch(lsvName, fileList, true, false);
asyncFileSearch.InvokeListView();
    
   

通过上述实现，用户在搜索过程中可以看到loading提示，避免了界面卡顿，同时提高了用户体验。

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