如果要将正则表达式限制为9个字符,则可以使用大括号,即
/^[0-9]{0,9}$/
To make a TextBox
take only 9 characters, you can specify it's MaxLength
attribute:
myTextBox.MaxLength = 9;
Then, if you only want the user to be able to enter numbers, handle the TextChanged
event:
myTextBox_TextChanged(object sender, EventArgs e)
{
if (Regex.IsMatch("[^0-9]",myTextBox.Text)
myTextBox.Text.Remove(myTextBox.Length - 1);
}
This checks if the last character of the TextBox
is not a number, and if it is not a number, removes it.
without regex I found my way out from this problem. below codes work awesome on my keydown event
else if (!(e.KeyValue >= 48 && e.KeyValue <= 57) || textBox1.Text.Length == 9)
{
e.SuppressKeyPress = !(e.KeyCode == Keys.Back || e.KeyCode == Keys.Left || e.KeyCode == Keys.Right);
}
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