OpenFileDialog 类

定义

public ref class OpenFileDialog sealed : System::Windows::Forms::FileDialog

public sealed class OpenFileDialog : System.Windows.Forms.FileDialog

type OpenFileDialog = class
    inherit FileDialog

Public NotInheritable Class OpenFileDialog
Inherits FileDialog

继承

Object

MarshalByRefObject

Component

CommonDialog

FileDialog

OpenFileDialog

示例

下面的代码示例创建 一个 OpenFileDialog，设置多个属性来定义文件扩展名筛选器和对话框行为，并使用 CommonDialog.ShowDialog 方法显示对话框。 该示例需要一个窗体，其中放置了 一个 Button ，并引用添加到该窗体的 System.IO 命名空间。

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

var fileContent = string.Empty;
var filePath = string.Empty;

using (OpenFileDialog openFileDialog = new OpenFileDialog())
{
    openFileDialog.InitialDirectory = "c:\\";
    openFileDialog.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";
    openFileDialog.FilterIndex = 2;
    openFileDialog.RestoreDirectory = true;

    if (openFileDialog.ShowDialog() == DialogResult.OK)
    {
        //Get the path of specified file
        filePath = openFileDialog.FileName;

        //Read the contents of the file into a stream
        var fileStream = openFileDialog.OpenFile();

        using (StreamReader reader = new StreamReader(fileStream))
        {
            fileContent = reader.ReadToEnd();
        }
    }
}

MessageBox.Show(fileContent, "File Content at path: " + filePath, MessageBoxButtons.OK);

Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
    Dim myStream As Stream = Nothing
    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() = System.Windows.Forms.DialogResult.OK Then
        Try
            myStream = openFileDialog1.OpenFile()
            If (myStream IsNot Nothing) Then
                ' Insert code to read the stream here.
            End If
        Catch Ex As Exception
            MessageBox.Show("Cannot read file from disk. Original error: " & Ex.Message)
        Finally
            ' Check this again, since we need to make sure we didn't throw an exception on open.
            If (myStream IsNot Nothing) Then
                myStream.Close()
            End If
        End Try
    End If
End Sub

注解

此类允许你检查文件是否存在并打开它。 属性ShowReadOnly确定对话框中是否显示只读检查框。 属性ReadOnlyChecked指示是否选中只读检查框。

此类的大多数核心功能都位于 类中 FileDialog 。

在从右到左的操作系统上，将包含窗体的 RightToLeft 属性设置为 RightToLeft.Yes 本地化对话框的 “文件名”、“ 打开”和“ 取消” 按钮。 如果 属性未设置为 RightToLeft.Yes，则改用英文文本。

如果要让用户能够选择文件夹而不是文件，请改用 FolderBrowserDialog 。

构造函数

属性

方法

事件

适用于

另请参阅

• FileDialog
• CommonDialog
• SaveFileDialog
• 如何：从文件中读取文本