C#-如何在此代码上创建非数字的异常
本文关键字:创建 数字 异常 代码 C#- | 更新日期: 2023-09-27 18:28:15
我想创建一个异常,当我键入非数字字符时,最好使用此代码中的Try/catch。我尝试过int.TryParse,但当我使用非数字字符时,它只返回0。但不要向我显示任何错误消息,但使用int.Parse(Console.ReadLine),我得到了一条错误消息:
输入字符字符串的格式不正确。
代码
while (true)
{
Console.WriteLine("TYPE A NUMBER HIGHER THAN 20: ");
int number;
number = int.Parse(Console.ReadLine());
if (number> 20)
{
Console.WriteLine("O NÚMERO DIGITADO FOI: " + number);
break;
}
else
{
Console.WriteLine(number+ " é menor do que 20, favor digitar um número maior");
}
}
Console.ReadLine();
您可以创建这样的异常:
Console.WriteLine("Type a number: ");
string line = Console.ReadLine();
try {
num = Int32.Parse(line);
}
catch (FormatException) {
Console.WriteLine("{0} is not an integer", line);
}
或者你可以使用int.TryParse
,正如你提到的:
Console.WriteLine("Type a number: ");
string line = Console.ReadLine();
if (!int.TryParse(line, out num)) {
Console.WriteLine("{0} is not an integer", line);
}
与其抛出异常,不如尝试使用Int32.TryParse(而不是Parse)处理输入:
bool run = true;
while (run)
{
Console.Write("Type in a number: ");
string input = Console.ReadLine();
//Exit application
if(input == "exit")
{
run = false;
return;
}
//Returns true if numberStr can be parsed to an int
int number;
if (Int32.TryParse(input, out number))
{
//input is a number, now let's do some logic!
if(number > 20)
Console.WriteLine("Number is greater than 20!");
else
Console.WriteLine("Number is less than 20!");
}
else
Console.WriteLine("Doesn't seem to be a number: " + number);
}
Console.ReadLine();