我尝试以这种方式执行一个函数,但是一旦它显示MessageBox
,它就会跳转到GUI并用最后一句说错误的消息。
if (!(double.TryParse(Waisttb.Text, out waist) && double.TryParse(Heighttb.Text, out height))) {
MessageBox.Show("Please enter a valid number!");
}
//no negative numbers
if (waist < 0 || height < 0) {
MessageBox.Show("Please enter a valid number!");
}
else {
//change to doubles
waist = double.Parse(Waisttb.Text);
}
答案 0 :(得分:2)
您必须重新排序逻辑。此外,重新解析已经解析的值没有用处。
if (!(double.TryParse(Waisttb.Text, out waist) && double.TryParse(Heighttb.Text, out height)))
{
// input is not a valid number
MessageBox.Show("Please enter a vailable number!");
}
else if (waist < 0 || height < 0)
{
// numbers are valid, but negative
MessageBox.Show("Please enter a vailable number!");
}
else
{
// numbers are valid and positive. use them here
}