SaveFileDialog.OverwritePrompt 屬性
定義
重要
部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。
取得或設定值，指出如果使用者指定已經存在的檔名，Save As 對話方塊是否顯示警告訊息。
public:
property bool OverwritePrompt { bool get(); void set(bool value); };public bool OverwritePrompt { get; set; }member this.OverwritePrompt : bool with get, setPublic Property OverwritePrompt As Boolean屬性值
如果使用者指定一個已經存在的檔名，在覆寫現有檔案之前對話方塊若會提示使用者，則為 true；如果對話方塊自動覆寫現有檔案而不提示使用者以取得使用權限，則為 false。 預設值是 true。
範例
下列程式碼範例示範如何搭配資料流程使用 RichTextBox.SaveFile 和 RichTextBox.LoadFile 方法。 它也會示範如何使用 FileName 、 DefaultExt 、 CreatePrompt 和 OverwritePrompt 成員。
這是當您將它複製到專案時所要執行的完整範例。
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
