有没有更简单的方法来格式化这个字符串？

Question

I've been attempting to format this string for a text box as it's getting typed in. The output result that I would like is as follows:

user presses '0' : output:'0 / / '

user presses '6' : output:'06/ / '

user presses '2' : output:'06/2 / '

etc.

What I currently have:

private void fTranDate_KeyPress(object sender, KeyPressEventArgs e)
{
    if(!Char.IsNumber(e.KeyChar) && !Char.IsControl(e.KeyChar) && fTranDate.Text.Length > 10)
    {
        e.Handled = true;
    }
    else if (!Char.IsControl(e.KeyChar)) //Is numeric
    {
        //Get the string from the field
        var existing_string = fTranDate.Text;
        //Strip the spaces and the slashes from the string
        existing_string = existing_string.Replace("/", "").Replace(" ","");
        //Append the new digit to the end of the string
        existing_string= existing_string + e.KeyChar;
        //Re-add the spaces on the end of the string
        existing_string = String.Format("{0,-8}", existing_string);

        var existing_char = existing_string.ToCharArray();
        fTranDate.Text = String.Format("{0}{1}/{2}{3}/{4}{5}{6}{7}", existing_char[0],existing_char[1],existing_char[2],existing_char[3],existing_char[4],existing_char[5],existing_char[6],existing_char[7]);
        fTranDate.SelectionStart = fTranDate.Text.Replace(" ","").Length;
        fTranDate.SelectionLength = 0;
        e.Handled = true;
    }
}

Is there any way to make this more streamlined? I've tried some other ideas but this is the only one that works.

Answer 1

You can use the MaskedTextbox with the input mask 00/00/0000 .

Edit you can also set the ValidatingType property to DateTime type.