Question

如果用户ID长度不匹配，如何允许用户重新输入该号码？

    for (int i = 0; i < 5; i++) {
        System.out.println("Enter the 5-digit ID number of your customer "
                + (i + 1) + "'s below:");
        customerID[i] = myScanner.nextLine();

        if (customerID[i].length() != 5) {
            // What code goes here. I just want to make it so they can
            // re-enter the customerID
        }

Answer 1

这是一种方法：

while(true)
{
    customerID[i] = myScanner.nextLine();
    if(customerID[i].length() == 5) break;
    System.out.print("Should be of length 5! Try Again: ");
}

Answer 2

（也许）最短的解决方案：

do
{
    customerID[i] = myScanner.nextLine();
} while(customerID[i].length() != 5);

Answer 3

你可以使用你拥有的循环。

for (int i = 0; i < 5; i++) {
    System.out.println("Enter the 5-digit ID number of your customer "
            + (i + 1) + "'s below:");
    customerID[i] = myScanner.nextLine();

    if (customerID[i].length() != 5) {
        // What code goes here. I just want to make it so they can
        // re-enter the customerID

        i--; // add this.
    }
}

Answer 4

试试这个。基本上，在有有效输入之前，不必增加索引。

int i = 0;
while( i < 5 ) {
 System.out.println("Enter the 5-digit ID number of your customer "
 + (i + 1) + "'s below:");
 customerID[i] = myScanner.nextLine();

 if (customerID[i].length() != 5) {
     /* Print an error and do not increment. 
      * The next line will overwrite the current one. */
 } else {
     /* Increment and move on */
     i++;
 }
}

如何将所需长度设置为数组中的整数？

4 个答案: