FileDialog.FilterIndex 属性

获取或设置文件对话框中当前选定筛选器的索引。

**命名空间:**System.Windows.Forms
**程序集:**System.Windows.Forms（在 system.windows.forms.dll 中）

语法

声明
Public Property FilterIndex As Integer
用法
Dim instance As FileDialog
Dim value As Integer

value = instance.FilterIndex

instance.FilterIndex = value

public int FilterIndex { get; set; }

public:
property int FilterIndex {
    int get ();
    void set (int value);
}

/** @property */
public int get_FilterIndex ()

/** @property */
public void set_FilterIndex (int value)

public function get FilterIndex () : int

public function set FilterIndex (value : int)

属性值

包含文件对话框中当前选定筛选器的索引的值。默认值为 1。

备注

使用 FilterIndex 属性设置第一个显示给用户的筛选选项。也可在显示文件对话框后使用 FilterIndex 的值，以根据选定的筛选器执行特殊的文件操作。

提示

第一个筛选器条目的索引值为 1。

示例

下面的代码示例使用 FileDialog 的 OpenFileDialog 实现，并演示如何创建和设置属性以及如何显示对话框。该示例使用 Filter 和 FilterIndex 属性为用户提供筛选器列表。该示例要求窗体上放置了一个 Button，并在其中添加了 System.IO 命名空间。

Private Sub button1_Click(sender As Object, e As System.EventArgs)
    Dim myStream As Stream
    Dim openFileDialog1 As New OpenFileDialog()
       
    openFileDialog1.InitialDirectory = "c:\"
    openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
    openFileDialog1.FilterIndex = 2
    openFileDialog1.RestoreDirectory = True
       
    If openFileDialog1.ShowDialog() = DialogResult.OK Then
        myStream = openFileDialog1.OpenFile()
        If Not (myStream Is Nothing) Then
            ' Insert code to read the stream here.
            myStream.Close()
        End If
    End If
End Sub

private void button1_Click(object sender, System.EventArgs e)
{
    Stream myStream;
    OpenFileDialog openFileDialog1 = new OpenFileDialog();

    openFileDialog1.InitialDirectory = "c:\\" ;
    openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*" ;
    openFileDialog1.FilterIndex = 2 ;
    openFileDialog1.RestoreDirectory = true ;

    if(openFileDialog1.ShowDialog() == DialogResult.OK)
    {
        if((myStream = openFileDialog1.OpenFile())!= null)
        {
            // Insert code to read the stream here.
            myStream.Close();
        }
    }
}

private:
   void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      Stream^ myStream;
      OpenFileDialog^ openFileDialog1 = gcnew OpenFileDialog;

      openFileDialog1->InitialDirectory = "c:\\";
      openFileDialog1->Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";
      openFileDialog1->FilterIndex = 2;
      openFileDialog1->RestoreDirectory = true;

      if ( openFileDialog1->ShowDialog() == ::DialogResult::OK )
      {
         if ( (myStream = openFileDialog1->OpenFile()) != nullptr )
         {
            // Insert code to read the stream here.
            myStream->Close();
         }
      }
   }

protected void button1_Click(Object sender, System.EventArgs e)
{
    Stream myStream;
    OpenFileDialog openFileDialog1 = new OpenFileDialog();
    openFileDialog1.set_InitialDirectory("c:\\");
    openFileDialog1.set_Filter(
        "txt files (*.txt)|*.txt|All files (*.*)|*.*");
    openFileDialog1.set_FilterIndex(2);
    openFileDialog1.set_RestoreDirectory(true);
    if (openFileDialog1.ShowDialog().Equals(get_DialogResult().OK)) {
        if ((myStream = openFileDialog1.OpenFile()) != null) {
            // Insert code to read the stream here.
            myStream.Close();
        }
    }
} //button1_Click

平台

Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0

.NET Compact Framework

受以下版本支持：2.0、1.0

请参见

参考

FileDialog 类
FileDialog 成员
System.Windows.Forms 命名空间
FileDialog.CheckFileExists 属性
FileDialog.Filter 属性