关于Java循环

时间:2018-09-04 23:08:17

标签: javascript loops for-loop if-statement

我想做什么

if(data){
var loop = var i = 0; i < arr.length; i++; // ASC
} else { 
loop = var i = arr.length-1; i > -1; i--; // DSC
}

for(loop){ ..content.. }

我该怎么做?

1 个答案:

答案 0 :(得分:1)

如果您要对数组进行排序,请查看.sort:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort

public static List<MyBean> GetRecords(String query){

    List<MyBean> myBeans = new ArrayList<>();
    //Executing query and saving result into result set
    try {
        stmt = con.createStatement();

        result = stmt.executeQuery(query);
        while (result.next()) {

            MyBean myBean = new MyBean();
            // Populate the bean...

            myBeans.add(myBean);
        }

    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    return myBeans;
}

如果您要从头开始而不是从头开始遍历整个数组,请签出.reverse:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reverse

const arr = [4, 2, 5, 1, 3];
const data = true;
    
if (data) {
  arr.sort((a, b) => a - b); // asc
} else {
  arr.sort((a, b) => b - a); // desc
}

console.log(arr)

在JavaScript中,您很少(尽管可以)使用标准的for循环,而是将.forEach,.reduce等迭代器与.reverse,.concat等数组函数结合使用。