private void rateTextBox_TextChanged(object sender, EventArgs e)
{
if (String.IsNullOrEmpty(pieceTextBox.Text))
{
}
else if (string.IsNullOrEmpty(rateReturnTextBox.Text))
{
}
else
{
int piece = Convert.ToInt32(pieceTextBox.Text);
int rate = Convert.ToInt32(rateTextBox.Text);
int netTotal = piece * rate;
netTotalBillTextBox.Text = netTotal.ToString();
}
}
/为什么不显示乘法答案......错误在哪里?
显然,在第二个条件下,不应该比较的是 rateTextBox
?
我想它总是会返回 string.Empty
在 rateReturnTextBox
.