java - 如何检查字符串以空格开头或结尾

Question

输入播放器名称。名称的长度必须介于 1 到 6 个字符之间，并且不能以空格字符开头或结尾。如果不符合要求，请重新输入名称。

import java.util.Scanner;

public class Player
{

    public void acceptName()
    {
        System.out.println("Please enter playrname");
        Scanner scanner = new Scanner(System.in);
        String playerName = scanner.nextLine();
        while(playerName.length() < 1 || playerName.length() > 6)
        {
            System.out.println("Name length over 6,Please re-enter playername");
            playerName = scanner.nextLine();
        }            
    }        
}

标签： java

Answer 1

You can check it with Character.isWhitespace() function:

if (Character.isWhitespace(playerName.charAt(0)) 
  || Character.isWhitespace(playerName.charAt(playerName.length() - 1)) {
   //do your stuff
}