Question

C# saveFileDialog1.FilterIndex和saveFileDialog1.RestoreDirectory

一个保存textbox1中内容的小程序 private void button2_Click(object sender, EventArgs e)        {            saveFileDialog1.Filter = "txt files (*.txt)|*.txt";            saveFileDialog1.FilterIndex = 2;            saveFileDialog1.RestoreDirectory = true;            if ((saveFileDialog1.ShowDialog() == DialogResult.OK))            {                if (textBox1.Text != null)                {                    {                        StreamWriter aWriter = new StreamWriter(saveFileDialog1.OpenFile());                        aWriter.Write(this.textBox1.Text);                        aWriter.Close(); 想问下saveFileDialog1.FilterIndex = 2;saveFileDialog1.RestoreDirectory = true;这两句具体是什么意思。

Answer 1

1.saveFileDialog1.Filter = "txt files (*.txt)|*.txt"; //只有1个滤字符串索引
saveFileDialog1.FilterIndex = 2; //设定显示的过滤字符串的索引,因为只有1个索引,所以设成2不会改变索引,还是第原来的"txt files (*.txt)|*.txt"
例: saveFileDialog1.Filter = "txt files (*.txt)|*.txt|exe files|*.exe|doc files|*.doc";//有三个滤字符串索引
saveFileDialog1.FilterIndex = 2; //索引设成2,那么当出现对话框时,文件保存类型,默认为"exe files"
2.saveFileDialog1.RestoreDirectory = true; 设为true时,对话框选择的目录会重新回到关闭此对话框时候的当前目录,就是点保存后,对话选择的默认目录为上次关闭时的目录