java - 切换选择错误的int案例

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Switch without break
                                
                                    （6个答案）
                                
                        
                                3年前关闭。
            
                    
我有这个简单的代码。一个值为0的整数和一个空字符串。很简单。但是，当我运行程序时，它将打印“ a”而不是“ z”。我不知道问题出在哪里，我想念什么。

public static void main(String[] args) {

    int classCode = 0;
    String classString = null;
    switch(classCode) {
    case 0:
        classString = "z";
    case 10:
        classString = "a";
        break;
    case 11:
        classString = "b";
        break;
    case 20:
        classString = "c";
        break;
    case 21:
        classString = "d";
        break;
    case 30:
        classString = "e ";
        break;
    case 31:
        classString = "f";
        break;
    }
    System.out.println(classString);

}

最佳答案

您已经忘记在第一种情况后加上break了。

switch(classCode) {
case 0:
    classString = "z";
    // missing a break here
case 10:
    classString = "a";
    break;