PS:最近在整理浏览器收藏夹中以前收藏的一些文章,把自己以前用到的或者感觉以后会用到的都转帖一下,勿拍砖。
本文通过五个步骤详细介绍C# WinForm 实现文件的拖入和拖出(拖拽操作),每个步骤都提供相关的示例代码供参考。
步骤1、放置一个 ListView 到 Winform窗体中 并初始化如下属性:
listView.View = View.Details;
listView.AllowDrop = true;
///
/// List files in the folder
///
/// the directory of the folder
private void ListFolder(string directory)
{
labelCurFolder.Text = directory;
String[] fileList = System.IO.Directory.GetFiles(directory);
listViewFolder.Items.Clear();
listViewFolder.Columns.Clear();
listViewFolder.Columns.Add(" Name ", 300);
listViewFolder.Columns.Add(" Size ", 100);
listViewFolder.Columns.Add(" Time ", 200);
foreach (string fileName in fileList)
{
// Show file name
ListViewItem itemName = new ListViewItem(System.IO.Path.GetFileName(fileName));
itemName.Tag = fileName;
// Show file icon
IconImageProvider iconImageProvider = new IconImageProvider(listViewFolder.SmallImageList, listViewFolder.LargeImageList);
itemName.ImageIndex = iconImageProvider.GetIconImageIndex(fileName);
// Show file size
System.IO.FileInfo fileInfo = new System.IO.FileInfo(fileName);
long size = fileInfo.Length;
String strSize;
if (size < 1024)
{
strSize = size.ToString();
}
else if (size < 1024 * 1024)
{
strSize = String.Format(" {0:###.##}KB ", (float)size / 1024);
}
else if (size < 1024 * 1024 * 1024)
{
strSize = String.Format(" {0:###.##}MB ", (float)size / (1024 * 1024));
}
else
{
strSize = String.Format(" {0:###.##}GB ", (float)size / (1024 * 1024 * 1024));
}
ListViewItem.ListViewSubItem subItem = new ListViewItem.ListViewSubItem();
subItem.Text = strSize;
subItem.Tag = size;
itemName.SubItems.Add(subItem);
// Show file time
subItem = new ListViewItem.ListViewSubItem();
DateTime fileTime = System.IO.File.GetLastWriteTime(fileName);
subItem.Text = (string)fileTime.ToLocalTime().ToString(" yyyy-MM-dd HH:mm:ss "); ;
subItem.Tag = fileTime;
itemName.SubItems.Add(subItem);
listViewFolder.Items.Add(itemName);
}
}
上面代码中有一段显示图标的代码由于和拖动无关,我就不贴出来了,感兴趣可以下载完整的代码去看。
private void listViewFolder_DragEnter(object sender, DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.FileDrop))
{
e.Effect = DragDropEffects.Copy;
}
else
{
e.Effect = DragDropEffects.None;
}
}
DragEnter 事件在其他应用程序拖入的文件进入时判断当前拖动的对象类型,如果是文件类型,则设置拖动响应类型为Copy。
private void listViewFolder_DragDrop(object sender, DragEventArgs e)
{
try
{
String[] files = e.Data.GetData(DataFormats.FileDrop, false) as String[];
// Copy file from external application
foreach (string srcfile in files)
{
string destFile = labelCurFolder.Text + " \\ " + System.IO.Path.GetFileName(srcfile);
if (System.IO.File.Exists(destFile))
{
if (MessageBox.Show(string.Format(
" This folder already contains a file named {0}," +
"would you like to replace the existing file ",
System.IO.Path.GetFileName(srcfile)),
" Confirm File Replace ",
MessageBoxButtons.YesNo,
MessageBoxIcon.None) != DialogResult.Yes)
{
continue;
}
}
System.IO.File.Copy(srcfile, destFile, true);
}
// List current folder
ListFolder();
}
catch (Exception e1)
{
MessageBox.Show(e1.Message, " Error ",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
DragDrop 事件在这里完成将其他应用程序拖入的文件拷贝到Winform应用当前的目录中。
private void listViewFolder_ItemDrag(object sender, ItemDragEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
if (listViewFolder.SelectedItems.Count <= 0)
{
return;
}
// put selected files into a string array
string[] files = new String[listViewFolder.SelectedItems.Count];
int i = 0;
foreach (ListViewItem item in listViewFolder.SelectedItems)
{
files[i++] = item.Tag.ToString();
}
// create a dataobject holding this array as a filedrop
DataObject data = new DataObject(DataFormats.FileDrop, files);
// also add the selection as textdata
data.SetData(DataFormats.StringFormat, files[0]);
// Do DragDrop
DoDragDrop(data, DragDropEffects.Copy);
}
}
From: http://dotnet.9sssd.com/winform/art/12