c# - 将 savedialog 的文件名附加到要保存的文件中

Question

我正在尝试在要保存的文本文件的第一行中附加文件名。我该怎么做？这是代码。我找不到 stringbuilder 在其实例开头附加的方法。

StringBuilder sb = new StringBuilder();

sb.AppendLine("BLAH BLAH");

if (saveFile.ShowDialog() == DialogResult.OK)
{
   //How to append file name at the beggining of the file to be saved?

    File.WriteAllText(saveFile.FileName, sb.ToString());
}

Answer 1

在调用 WriteAllText 之前添加这一行：

sb.Insert(0, saveFile.FileName + Environment.NewLine);

- 或者 -

string outString = saveFile.FileName + Environment.NewLine + sb.ToString();  
File.WriteAllText(saveFile.FileName, outString);

Answer 2

要保留以前的文本：

StringBuilder sb = new StringBuilder();

// Appending string to your StringBuilder string value.
sb.AppendLine("BLAH BLAH");

if (saveFile.ShowDialog() == DialogResult.OK)
{
    // Keep the previous file text .. By inserting it in the begining of the 
    // StringBuilder string value. 
    sb.Insert(0, File.ReadAllText(saveFile.FileName) + Environment.NewLine);

    // Insert File Name in the begining of the StringBuilder string value.
    sb.Insert(0, saveFile.FileName + Environment.NewLine);

    File.WriteAllText(saveFile.FileName, sb.ToString());
}