c#记事本

Question

我是编程新手，我开始创建一个简单的记事本，只有4个按钮(打开，保存，新建和字体)。

如果我打开或保存，我得到一个错误:这是我的代码：

        //Declare save as a new SaveFileDailog
        SaveFileDialog save = new SaveFileDialog();
        //Declare filename as a String equal to the SaveFileDialog's FileName
        String filename = save.FileName;
        //Declare filter as a String equal to our wanted SaveFileDialog Filter
        String filter = "Text Files|*.txt|All Files|*.*";
        //Set the SaveFileDialog's Filter to filter
        save.Filter = filter;
        //Set the title of the SaveFileDialog to Save
        save.Title = "Save";
        //Show the SaveFileDialog
        if (save.ShowDialog(this) == DialogResult.OK)
        {
            //Write all of the text in txtBox to the specified file
            System.IO.File.WriteAllText(filename, textBox1.Text);
        }
        else
        {
            //Return
            return;
        }//Declare save as a new SaveFileDailog
        SaveFileDialog save = new SaveFileDialog();
        //Declare filename as a String equal to the SaveFileDialog's FileName
        String filename = save.FileName;
        //Declare filter as a String equal to our wanted SaveFileDialog Filter
        String filter = "Text Files|*.txt|All Files|*.*";
        //Set the SaveFileDialog's Filter to filter
        save.Filter = filter;
        //Set the title of the SaveFileDialog to Save
        save.Title = "Save";
        //Show the SaveFileDialog
        if (save.ShowDialog(this) == DialogResult.OK)
        {
            //Write all of the text in txtBox to the specified file
            System.IO.File.WriteAllText(filename, textBox1.Text);
        }
        else
        {
            //Return
            return;
        }

有什么想法吗？感谢并致以问候

ooopss我忘记写错误了，对此我很抱歉:这是错误：“错误: ArgumentException未处理。空路径名不合法”

如果我打开一个文本文件，就会得到这样的结果。然后突出显示这一行代码: textBox1.Text=System.IO.File.ReadAllText(filename，System.Text.Encoding.Default)；

如果我保存的话什么都不会发生。

谢谢

Answer 1

我希望在用户使用该对话框之后，您应该正在读取文件名：

System.IO.File.WriteAllText(save.FileName, textBox1.Text);

还有- SaveFileDialog是IDisposable，所以你应该是"using“它...

using (SaveFileDialog save = new SaveFileDialog())
{
    // your code that involves "save"
}

Answer 2

尝试移动这条线

String filename = save.FileName;

在IF块内部。在用户设置SaveDialog的属性之前，您正在为filename赋值。您需要了解，此行不会在您的filename变量和对话框的FileName属性之间创建永久链接。

Answer 3

在调用ShowDialog之后，您可以从SaveFileDialog 获取文件名。您正在预先设置文件名。