textbox只能输入数字
方法一：
private void textBox7_KeyPress(object sender, KeyPressEventArgs e)//只能输入数字和.
{
byte[] array = System.Text.Encoding.Default.GetBytes(e.KeyChar.ToString());
if (!char.IsDigit(e.KeyChar) || array.LongLength == 2) e.Handled = true;
if (e.KeyChar == '/b' || e.KeyChar == '.') e.Handled = false;
}
方法二：
private void textBox7_KeyPress(object sender, KeyPressEventArgs e)//只能输入数字和. 但不能输入小数
{
if (!(e.KeyChar >= '0' && e.KeyChar <= '9')) e.Handled = true;
if (e.KeyChar == '/b' || e.KeyChar == '.') e.Handled = false;
}
方法三：
private void textBox7_KeyPress(object sender, KeyPressEventArgs e)//需求数量栏位，只能输入数字，并且可以输入小数
{
if (e.KeyChar != 13 && e.KeyChar != 8 && !char.IsDigit(e.KeyChar) && e.KeyChar != 46) e.Handled = true;
int a = textBox7.Text.IndexOf('.');
if (e.KeyChar == 46 && a > 0) e.Handled = true;
}