SaveFileDialog错误

Question

我正在尝试制作一个保存文本文件的简单Windows窗体应用程序。我在下面的程序上遇到了麻烦，它给了我：

空路径是不合法的

namespace Filing
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void button_Save_Click(object sender, EventArgs e)
        {

            SaveFileDialog file = new SaveFileDialog();

            file.Filter = "Text (*.txt) | Word File *.doc";
            file.Title = "Save a file";
            File.WriteAllText(file.FileName, richTextBox1.Text);

            file.ShowDialog();
        }

        private void button_exit_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }
}

Answer 1

因为您还没有“显示”SaveFileDialog，所以fileName是空的。

尝试将showDialog向上移动：

private void button_Save_Click(object sender, EventArgs e)
    {

        SaveFileDialog file = new SaveFileDialog();

        file.Filter = "Text (*.txt) | Word File *.doc";
        file.Title = "Save a file";
        //Ask the user to select the file path and file name, don't forget to handle cancel button!
        if(file.ShowDialog() != DialogResult.Cancel)
        {
              File.WriteAllText(file.FileName, richTextBox1.Text);
        }
    }

Answer 2

您应该将写入语句包装如下。

if(file.ShowDialog()== DialogResult.OK)
     File.WriteAllText(file.FileName, richTextBox1.Text);