请在一个类中编写一个方法,这个方法搜索一个字符数组中是否存在某个字符,如果存在,
则返回这个字符在字符数组中第一次出现的位置(序号从0开始计算),否则,返回-1。
要搜索的字符数组和字符都以参数形式传递传递给该方法,如果传入的数组为null,
应抛出IllegalArgumentException异常。在类的main方法中以各种可能出现的情况测试验证该方法编写得是否正确,
例如,字符不存在,字符存在,传入的数组为null等。
不用indexOf()等方法;

解决方案 »

  1.   

    写个方法,将他搜索的字符当方法的参数就可以了,写个思路给你,自己补充一下
    public int check(char a){
       int flag = 0;
       for(int j = 0;j<charByte.length;j++){
        if(a == charByte[i]){
           flag = 1;
        }else{
           flag = -1;
        }
      }
      return flag
    }
      

  2.   

    不好实现啊,你想的这我也写过。假如 a b c 三个字符,你搜索b 当搜索完a后就返回-1了;
      

  3.   

    建议你去看看indexOf,这跟用不用indexOf有什么关系吗?
    你自己不会实现indexOf吗?
      

  4.   

    class Index                                                
     {                                                          
       public int check(char c,char[] a)                        
       {                                                        
           int pos=-1;                                          
           if(a==null)                                          
            throw new IllegalArgumentException();               
           else                                                 
            {    for(int i=0;i<a.length;i++)                    
               {                                                
                if(c==(a[i]))                                   
                 {                                              
                   pos=i;                                       
                  return pos;                                   
                  }                                             
               }                                                
           }                                                    
           return pos;                                          
        }                                                       
       public static void main(String[] args)                   
       {                                                        
        //检验方法是否正确:
        char[] a={'a','b','c','d','e','f','g','h'};             
        int pos=0;                                              
        pos=new Index().check('a',a);                     
        //pos=new Index().check('c',null);                      
        System.out.println(pos);                                
       }                                                        
    }                                                           
      

  5.   

    谢谢,我一直没想到int pos=-1; 晕!