RichTextBox.LoadFile 方法

参考

定义

命名空间:: System.Windows.Forms

程序集:: System.Windows.Forms.dll

重要

一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。

将文件的内容加载到 RichTextBox 控件中。

重载

LoadFile(String)	将 RTF 格式文件或标准 ASCII 文本文件加载到 RichTextBox 控件中。
LoadFile(Stream, RichTextBoxStreamType)	将现有数据流的内容加载到 RichTextBox 控件中。
LoadFile(String, RichTextBoxStreamType)	将特定类型的文件加载到 RichTextBox 控件中。

LoadFile(String)

将 RTF 格式文件或标准 ASCII 文本文件加载到 RichTextBox 控件中。

public:
 void LoadFile(System::String ^ path);

public void LoadFile (string path);

member this.LoadFile : string -> unit

Public Sub LoadFile (path As String)

参数

path: String

要加载到控件中的文件的名称和位置。

例外

IOException

将文件加载到控件中时出现错误。

ArgumentException

所加载的文件不是 RTF 文档。

示例

下面的代码示例在控件中 RichTextBox 打开一个 RTF 文件。该示例使用 OpenFileDialog 类显示一个对话框来请求用户的文件。然后，代码加载该文件，假设它是 RTF 文档文件。如果文件不是，则示例代码将引发异常。此示例要求将代码放置在具有RichTextBox名为的控件的richTextBox1类中Form。

public:
   void LoadMyFile()
   {
      // Create an OpenFileDialog to request a file to open.
      OpenFileDialog^ openFile1 = gcnew OpenFileDialog;
      
      // Initialize the OpenFileDialog to look for RTF files.
      openFile1->DefaultExt = "*.rtf";
      openFile1->Filter = "RTF Files|*.rtf";
      
      // Determine whether the user selected a file from the OpenFileDialog.
      if ( openFile1->ShowDialog() == System::Windows::Forms::DialogResult::OK &&
         openFile1->FileName->Length > 0 )
      {
         // Load the contents of the file into the RichTextBox.
         richTextBox1->LoadFile( openFile1->FileName );
      }
   }

public void LoadMyFile()
{
   // Create an OpenFileDialog to request a file to open.
   OpenFileDialog openFile1 = new OpenFileDialog();

   // Initialize the OpenFileDialog to look for RTF files.
   openFile1.DefaultExt = "*.rtf";
   openFile1.Filter = "RTF Files|*.rtf";

   // Determine whether the user selected a file from the OpenFileDialog.
   if(openFile1.ShowDialog() == System.Windows.Forms.DialogResult.OK &&
      openFile1.FileName.Length > 0) 
   {
      // Load the contents of the file into the RichTextBox.
      richTextBox1.LoadFile(openFile1.FileName);
   }
}

Public Sub LoadMyFile()
    ' Create an OpenFileDialog to request a file to open.
    Dim openFile1 As New OpenFileDialog()
    
    ' Initialize the OpenFileDialog to look for RTF files.
    openFile1.DefaultExt = "*.rtf"
    openFile1.Filter = "RTF Files|*.rtf"
    
    ' Determine whether the user selected a file from the OpenFileDialog.
    If (openFile1.ShowDialog() = System.Windows.Forms.DialogResult.OK) _
        And (openFile1.FileName.Length > 0) Then
        
        ' Load the contents of the file into the RichTextBox.
        richTextBox1.LoadFile(openFile1.FileName)
    End If
End Sub

注解

使用 LoadFile 方法加载文件时，要加载的文件的内容将替换控件的 RichTextBox 整个内容。这将导致和 Rtf 属性的值Text发生更改。可以使用此方法将以前创建的文本或 RTF 文档加载到控件中以便进行操作。如果要保存文件，可以使用 SaveFile 方法。

注意

使用此方法的 LoadFile 此版本时，如果加载的文件不是 RTF 文档，则会发生异常。若要加载不同类型的文件（如 ASCII 文本文件），请使用此方法的其他版本，该方法接受枚举中的 RichTextBoxStreamType 值作为参数。

注意

在 LoadFile 为创建句柄之前， RichTextBox方法不会打开文件。确保在调用方法之前创建控件的句 LoadFile 柄。

另请参阅

SaveFile(String)

适用于

LoadFile(Stream, RichTextBoxStreamType)

将现有数据流的内容加载到 RichTextBox 控件中。

public:
 void LoadFile(System::IO::Stream ^ data, System::Windows::Forms::RichTextBoxStreamType fileType);

public void LoadFile (System.IO.Stream data, System.Windows.Forms.RichTextBoxStreamType fileType);

member this.LoadFile : System.IO.Stream * System.Windows.Forms.RichTextBoxStreamType -> unit

Public Sub LoadFile (data As Stream, fileType As RichTextBoxStreamType)

参数

data: Stream

要加载到 RichTextBox 控件中的数据流。

fileType: RichTextBoxStreamType

RichTextBoxStreamType 值之一。

例外

IOException

将文件加载到控件中时出现错误。

ArgumentNullException

.NET 5 及更高版本：参数 data 为 null。

ArgumentException

所加载的文件不是 RTF 文档。

示例

下面的代码示例演示如何将和 LoadFile 方法与流配合使用SaveFile。它还演示了如何使用 FileDialog.FileName、 FileDialog.DefaultExt、 SaveFileDialog.CreatePrompt和 SaveFileDialog.OverwritePrompt 成员。

这是一个完整示例，可在将它复制到项目时运行。

using namespace System;
using namespace System::Drawing;
using namespace System::IO;
using namespace System::Windows::Forms;

public ref class Form1: public Form
{
public private:
   RichTextBox^ RichTextBox1;
   Button^ Button1;
   RichTextBox^ RichTextBox2;
   Button^ Button2;
   SaveFileDialog^ SaveFileDialog1;

public:
   Form1()
      : Form()
   {
      userInput = gcnew MemoryStream;
      this->RichTextBox1 = gcnew RichTextBox;
      this->Button1 = gcnew Button;
      this->RichTextBox2 = gcnew RichTextBox;
      this->Button2 = gcnew Button;
      this->SaveFileDialog1 = gcnew SaveFileDialog;
      this->SuspendLayout();
      this->RichTextBox1->Location = Point( 24, 64 );
      this->RichTextBox1->Name = "RichTextBox1";
      this->RichTextBox1->TabIndex = 0;
      this->RichTextBox1->Text = "Type something here.";
      this->Button1->Location = Point( 96, 16 );
      this->Button1->Name = "Button1";
      this->Button1->Size = Size( 96, 24 );
      this->Button1->TabIndex = 1;
      this->Button1->Text = "Save To Stream";
      this->Button1->Click += 
          gcnew EventHandler( this, &Form1::Button1_Click );
      this->RichTextBox2->Location = Point( 152, 64 );
      this->RichTextBox2->Name = "RichTextBox2";
      this->RichTextBox2->TabIndex = 3;
      this->RichTextBox2->Text = "It will be added to the stream "
      "and appear here.";
      this->Button2->Location = Point( 104, 200 );
      this->Button2->Name = "Button2";
      this->Button2->Size = Size( 88, 32 );
      this->Button2->TabIndex = 4;
      this->Button2->Text = "Save Stream To File";
      this->Button2->Click += 
          gcnew EventHandler( this, &Form1::Button2_Click );
      this->ClientSize = Size( 292, 266 );
      this->Controls->Add( this->Button2 );
      this->Controls->Add( this->RichTextBox2 );
      this->Controls->Add( this->Button1 );
      this->Controls->Add( this->RichTextBox1 );
      this->Name = "Form1";
      this->Text = "Form1";
      this->ResumeLayout( false );
   }

   // Declare a new memory stream.
   MemoryStream^ userInput;

private:

   // Save the content of RichTextBox1 to the memory stream, 
   // appending a LineFeed character.  
   void Button1_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      RichTextBox1->SaveFile( userInput, RichTextBoxStreamType::PlainText );
      userInput->WriteByte( 13 );
      
      // Display the entire contents of the stream,
      // by setting its position to 0, to RichTextBox2.
      userInput->Position = 0;
      RichTextBox2->LoadFile( userInput, RichTextBoxStreamType::PlainText );
   }


   // Shows the use of a SaveFileDialog to save a MemoryStream to a file.
   void Button2_Click( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      
      // Set the properties on SaveFileDialog1 so the user is 
      // prompted to create the file if it doesn't exist 
      // or overwrite the file if it does exist.
      SaveFileDialog1->CreatePrompt = true;
      SaveFileDialog1->OverwritePrompt = true;
      
      // Set the file name to myText.txt, set the type filter
      // to text files, and set the initial directory to the
      // MyDocuments folder.
      SaveFileDialog1->FileName = "myText";
      // DefaultExt is only used when "All files" is selected from 
      // the filter box and no extension is specified by the user.
      SaveFileDialog1->DefaultExt = "txt";
      SaveFileDialog1->Filter = "Text files (*.txt)|*.txt|All files (*.*)|*.*";
      SaveFileDialog1->InitialDirectory = 
          Environment->GetFolderPath(Environment::SpecialFolder::MyDocuments);
      
      // Call ShowDialog and check for a return value of DialogResult.OK,
      // which indicates that the file was saved. 
      DialogResult result = SaveFileDialog1->ShowDialog();
      Stream^ fileStream;
      if ( result == DialogResult::OK )
      {
         fileStream = SaveFileDialog1->OpenFile();
         userInput->Position = 0;
         userInput->WriteTo( fileStream );
         fileStream->Close();
      }
   }
};

int main()
{
   Application::Run( gcnew Form1 );
}

using System;
using System.Drawing;
using System.IO;
using System.Windows.Forms;

public partial class Form1: Form
{
    internal RichTextBox RichTextBox1;
    internal Button Button1;
    internal RichTextBox RichTextBox2;
    internal Button Button2;
    internal SaveFileDialog SaveFileDialog1;

    public Form1() : base()
    {   
        this.RichTextBox1 = new RichTextBox();
        this.Button1 = new Button();
        this.RichTextBox2 = new RichTextBox();
        this.Button2 = new Button();
        this.SaveFileDialog1 = new SaveFileDialog();
        this.SuspendLayout();
        this.RichTextBox1.Location = new Point(24, 64);
        this.RichTextBox1.Name = "RichTextBox1";
        this.RichTextBox1.TabIndex = 0;
        this.RichTextBox1.Text = "Type something here.";
        this.Button1.Location = new Point(96, 16);
        this.Button1.Name = "Button1";
        this.Button1.Size = new Size(96, 24);
        this.Button1.TabIndex = 1;
        this.Button1.Text = "Save To Stream";
        this.Button1.Click += new EventHandler(Button1_Click);
        this.RichTextBox2.Location = new Point(152, 64);
        this.RichTextBox2.Name = "RichTextBox2";
        this.RichTextBox2.TabIndex = 3;
        this.RichTextBox2.Text = 
            "It will be added to the stream and appear here.";
        this.Button2.Location = new Point(104, 200);
        this.Button2.Name = "Button2";
        this.Button2.Size = new Size(88, 32);
        this.Button2.TabIndex = 4;
        this.Button2.Text = "Save Stream To File";
        this.Button2.Click += new EventHandler(Button2_Click);
        this.ClientSize = new Size(292, 266);
        this.Controls.Add(this.Button2);
        this.Controls.Add(this.RichTextBox2);
        this.Controls.Add(this.Button1);
        this.Controls.Add(this.RichTextBox1);
        this.Name = "Form1";
        this.Text = "Form1";
        this.ResumeLayout(false);
    }

    public static void Main()
    {
        Application.Run(new Form1());
    }

    // Declare a new memory stream.
    MemoryStream userInput = new MemoryStream();

    // Save the content of RichTextBox1 to the memory stream, 
    // appending a LineFeed character.  
    private void Button1_Click(Object sender, EventArgs e)
    {
        RichTextBox1.SaveFile(userInput, RichTextBoxStreamType.PlainText);
        userInput.WriteByte(13);

        // Display the entire contents of the stream,
        // by setting its position to 0, to RichTextBox2.
        userInput.Position = 0;
        RichTextBox2.LoadFile(userInput, RichTextBoxStreamType.PlainText);
    }

    // Shows the use of a SaveFileDialog to save a MemoryStream to a file.
    private void Button2_Click(Object sender, EventArgs e)
    {
        // Set the properties on SaveFileDialog1 so the user is 
        // prompted to create the file if it doesn't exist 
        // or overwrite the file if it does exist.
        SaveFileDialog1.CreatePrompt = true;
        SaveFileDialog1.OverwritePrompt = true;

        // Set the file name to myText.txt, set the type filter
        // to text files, and set the initial directory to the 
        // MyDocuments folder.
        SaveFileDialog1.FileName = "myText";
        // DefaultExt is only used when "All files" is selected from 
        // the filter box and no extension is specified by the user.
        SaveFileDialog1.DefaultExt = "txt";
        SaveFileDialog1.Filter = 
            "Text files (*.txt)|*.txt|All files (*.*)|*.*";
        SaveFileDialog1.InitialDirectory = 
            Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);

        // Call ShowDialog and check for a return value of DialogResult.OK,
        // which indicates that the file was saved. 
        DialogResult result = SaveFileDialog1.ShowDialog();
        Stream fileStream;

        if (result == DialogResult.OK)
        {
            // Open the file, copy the contents of memoryStream to fileStream,
            // and close fileStream. Set the memoryStream.Position value to 0 
            // to copy the entire stream. 
            fileStream = SaveFileDialog1.OpenFile();
            userInput.Position = 0;
            userInput.WriteTo(fileStream);
            fileStream.Close();
        }
    }
}

Imports System.Drawing
Imports System.IO
Imports System.Windows.Forms

Partial Public Class Form1
    Inherits Form

    Friend WithEvents RichTextBox1 As RichTextBox
    Friend WithEvents Button1 As Button
    Friend WithEvents RichTextBox2 As RichTextBox
    Friend WithEvents Button2 As Button
    Friend WithEvents SaveFileDialog1 As SaveFileDialog

    Public Sub New()
        MyBase.New()
        Me.RichTextBox1 = New RichTextBox
        Me.Button1 = New Button
        Me.RichTextBox2 = New RichTextBox
        Me.Button2 = New Button
        Me.SaveFileDialog1 = New SaveFileDialog
        Me.SuspendLayout()
        Me.RichTextBox1.Location = New Point(24, 64)
        Me.RichTextBox1.Name = "RichTextBox1"
        Me.RichTextBox1.TabIndex = 0
        Me.RichTextBox1.Text = "Type something here."
        Me.Button1.Location = New Point(96, 16)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New Size(96, 24)
        Me.Button1.TabIndex = 1
        Me.Button1.Text = "Save To Stream"
        Me.RichTextBox2.Location = New Point(152, 64)
        Me.RichTextBox2.Name = "RichTextBox2"
        Me.RichTextBox2.TabIndex = 3
        Me.RichTextBox2.Text = "It will be added to the stream and appear here."
        Me.Button2.Location = New Point(104, 200)
        Me.Button2.Name = "Button2"
        Me.Button2.Size = New Size(88, 32)
        Me.Button2.TabIndex = 4
        Me.Button2.Text = "Save Stream To File"
        Me.ClientSize = New Size(292, 266)
        Me.Controls.Add(Me.Button2)
        Me.Controls.Add(Me.RichTextBox2)
        Me.Controls.Add(Me.Button1)
        Me.Controls.Add(Me.RichTextBox1)
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)

    End Sub

    Public Shared Sub Main()
        Application.Run(New Form1)
    End Sub

    ' Declare a new memory stream.
    Dim userInput As New MemoryStream

    ' Save the content of RichTextBox1 to the memory stream, appending
    'a LineFeed character.  
    Private Sub Button1_Click(ByVal sender As Object, _
        ByVal e As EventArgs) Handles Button1.Click
        RichTextBox1.SaveFile(userInput, RichTextBoxStreamType.PlainText)
        userInput.WriteByte(13)

        ' Display the entire contents of the stream,
        ' by setting its position to 0, to RichTextBox2.
        userInput.Position = 0
        RichTextBox2.LoadFile(userInput, RichTextBoxStreamType.PlainText)
    End Sub

    ' Shows the use of a SaveFileDialog to save a MemoryStream to a file.
    Private Sub Button2_Click(ByVal sender As Object, _
        ByVal e As EventArgs) Handles Button2.Click

        ' Set the properties on SaveFileDialog1 so the user is 
        ' prompted to create the file if it doesn't exist 
        ' or overwrite the file if it does exist.
        SaveFileDialog1.CreatePrompt = True
        SaveFileDialog1.OverwritePrompt = True

        ' Set the file name to myText.txt, set the type filter
        ' to text files, and set the initial directory to the 
        ' MyDocuments folder.
        SaveFileDialog1.FileName = "myText"
        ' DefaultExt is only used when "All files" is selected from 
        ' the filter box and no extension is specified by the user.
        SaveFileDialog1.DefaultExt = "txt"
        SaveFileDialog1.Filter = "Text files (*.txt)|*.txt|All files (*.*)|*.*"
        SaveFileDialog1.InitialDirectory = _
            Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)

        ' Call ShowDialog and check for a return value of DialogResult.OK,
        ' which indicates that the file was saved. 
        Dim result As DialogResult = SaveFileDialog1.ShowDialog()
        Dim fileStream As Stream

        If (result = DialogResult.OK) Then
            ' Open the file, copy the contents of memoryStream to fileStream,
            ' and close fileStream. Set the memoryStream.Position value to 0 to 
            ' copy the entire stream. 
            fileStream = SaveFileDialog1.OpenFile()
            userInput.Position = 0
            userInput.WriteTo(fileStream)
            fileStream.Close()
        End If
    End Sub

End Class

注解

可以使用此版本的 LoadFile 方法从现有数据流加载 RichTextBox 数据。加载到控件中的数据将替换控件的 RichTextBox 整个内容。这将导致和 Rtf 属性的值Text发生更改。可以使用此方法将以前打开的数据流中的文件加载到控件中以进行操作。如果要将控件的内容保存回流中，可以使用 SaveFile 接受 Stream 对象作为参数的方法。

此方法的 LoadFile 此版本还可用于指定要加载到控件中的数据类型。借助此功能，可以使用包含格式文本格式以外的数据的数据流， (RTF) 文档中的控件。

注意

在 LoadFile 为创建句柄之前， RichTextBox方法不会打开文件。确保在调用方法之前创建控件的句 LoadFile 柄。

另请参阅

适用于

LoadFile(String, RichTextBoxStreamType)

将特定类型的文件加载到 RichTextBox 控件中。

public:
 void LoadFile(System::String ^ path, System::Windows::Forms::RichTextBoxStreamType fileType);

public void LoadFile (string path, System.Windows.Forms.RichTextBoxStreamType fileType);

member this.LoadFile : string * System.Windows.Forms.RichTextBoxStreamType -> unit

Public Sub LoadFile (path As String, fileType As RichTextBoxStreamType)

参数

path: String

要加载到控件中的文件的名称和位置。

fileType: RichTextBoxStreamType

RichTextBoxStreamType 值之一。

例外

IOException

将文件加载到控件中时出现错误。

ArgumentException

所加载的文件不是 RTF 文档。

示例

下面的代码示例在控件中 RichTextBox 打开一个文本文件。该示例使用 OpenFileDialog 类显示一个对话框来请求用户的文件。然后，代码会将该文件加载到控件中 RichTextBox 。该示例使用此版本的 LoadFile 方法指定文件作为 ASCII 文本文件而不是标准格式格式打开。此示例要求将代码放置在具有RichTextBox名为的控件的richTextBox1类中Form。

public:
   void LoadMyFile()
   {
      // Create an OpenFileDialog to request a file to open.
      OpenFileDialog^ openFile1 = gcnew OpenFileDialog;
      
      // Initialize the OpenFileDialog to look for RTF files.
      openFile1->DefaultExt = "*.rtf";
      openFile1->Filter = "RTF Files|*.rtf";
      
      // Determine whether the user selected a file from the OpenFileDialog.
      if ( openFile1->ShowDialog() == System::Windows::Forms::DialogResult::OK &&
         openFile1->FileName->Length > 0 )
      {
         // Load the contents of the file into the RichTextBox.
         richTextBox1->LoadFile( openFile1->FileName, RichTextBoxStreamType::PlainText );
      }
   }

public void LoadMyFile()
{
   // Create an OpenFileDialog to request a file to open.
   OpenFileDialog openFile1 = new OpenFileDialog();

   // Initialize the OpenFileDialog to look for RTF files.
   openFile1.DefaultExt = "*.rtf";
   openFile1.Filter = "RTF Files|*.rtf";

   // Determine whether the user selected a file from the OpenFileDialog.
   if(openFile1.ShowDialog() == System.Windows.Forms.DialogResult.OK &&
      openFile1.FileName.Length > 0) 
   {
      // Load the contents of the file into the RichTextBox.
      richTextBox1.LoadFile(openFile1.FileName, RichTextBoxStreamType.PlainText);
   }
}

Public Sub LoadMyFile()
    ' Create an OpenFileDialog to request a file to open.
    Dim openFile1 As New OpenFileDialog()
    
    ' Initialize the OpenFileDialog to look for RTF files.
    openFile1.DefaultExt = "*.rtf"
    openFile1.Filter = "RTF Files|*.rtf"
    
    ' Determine whether the user selected a file from the OpenFileDialog.
    If (openFile1.ShowDialog() = System.Windows.Forms.DialogResult.OK) _
        And (openFile1.FileName.Length > 0) Then
        
        ' Load the contents of the file into the RichTextBox.
        richTextBox1.LoadFile(openFile1.FileName, _
            RichTextBoxStreamType.PlainText)
    End If
End Sub

注解

使用 LoadFile 方法加载文件时，要加载的文件的内容将替换控件的 RichTextBox 整个内容。这将导致和 Rtf 属性的值Text发生更改。可以使用此方法将以前创建的文本或格式文本 (RTF) 文档加载到控件中以进行操作。如果要保存文件，可以使用 SaveFile 方法。

可以使用此版本的 LoadFile 方法指定要加载的文件的文件类型。使用此功能可将 RTF 文档以外的文件加载到控件中。

注意

在 LoadFile 为创建句柄之前， RichTextBox方法不会打开文件。确保在调用方法之前创建控件的句 LoadFile 柄。

另请参阅

适用于

通过

RichTextBox.LoadFile 方法

定义

重载

LoadFile(String)

参数

例外

示例

注解

另请参阅

适用于

LoadFile(Stream, RichTextBoxStreamType)

参数

例外

示例

注解

另请参阅

适用于

LoadFile(String, RichTextBoxStreamType)

参数

例外

示例

注解

另请参阅

适用于

其他资源