怎么实现这个功能

Question

很简单的！
看一下File类的使用介绍你就明白了！

Answer 1

private void OpenFile()
{
dlgOpen.Filter="RTF文件(*.rtf)|*.rtf";
if(dlgOpen.ShowDialog()==DialogResult.OK)
{
vNewFile="0";
sFileName=dlgOpen.FileName;
rtBox.LoadFile(sFileName,RichTextBoxStreamType.RichText);
this.Text="File—"+sFileName;
}
}private void SaveFile()
{
dlgSave.DefaultExt="*.rtf";
dlgSave.Filter="RTF文件|*.rtf";
if(vNewFile=="1")
         if(dlgSave.ShowDialog()==DialogResult.OK)
                   sFileName=dlgSave.FileName;
if(sFileName.Length > 0) 
{
         this.Text="File—"+sFileName;
rtBox.SaveFile(sFileName,RichTextBoxStreamType.RichText);
}
}

Answer 2

private void OpenFile()
{
dlgOpen.Filter="RTF文件(*.rtf)|*.rtf";
if(dlgOpen.ShowDialog()==DialogResult.OK)
{
vNewFile="0";
sFileName=dlgOpen.FileName;
rtBox.LoadFile(sFileName,RichTextBoxStreamType.RichText);
this.Text="File—"+sFileName;
}
}private void SaveFile()
{
dlgSave.DefaultExt="*.rtf";
dlgSave.Filter="RTF文件|*.rtf";
if(vNewFile=="1")
         if(dlgSave.ShowDialog()==DialogResult.OK)
                   sFileName=dlgSave.FileName;
if(sFileName.Length > 0) 
{
         this.Text="File—"+sFileName;
rtBox.SaveFile(sFileName,RichTextBoxStreamType.RichText);
}
}
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