Question

请你看一下这个演示，让我知道如何循环到sectorArray[]的不同元素并在按钮点击触发时记录元素？现在我遇到一个问题，即在函数到达最后一个元素时，从减号或加号开始并返回到开头！

＆＃13;

var sectorArray = ["a", "b", "c"];
var counter = 0;
$(".plus").on("click", function(e) {
  console.log(sectorArray[counter]);
  counter++;
});
$(".minus").on("click", function(e) {
  counter--;
  console.log(sectorArray[counter]);

});

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
    <button type="button" class="minus">-</button>
    <button type="button" class="plus" >+</button>

＆＃13;

Answer 1

working fiddle

您需要做的就是在counter变量超出范围时重置它：

var sectorArray = ["a", "b", "c"];
var counter = -1; // start at -1 because we inc/dec before we log

$(".plus").on("click", function(e) {
  // Increment and check if counter is out of bounds
  if(++counter >= sectorArray.length){
    counter = 0;
  }
  console.log(sectorArray[counter]);
});

$(".minus").on("click", function(e) {
  // Decrement and check if counter is out of bounds
  if(--counter < 0){
    counter = sectorArray.length - 1;
  }
  console.log(sectorArray[counter]);
});

有问题通过数组循环来记录Click上的元素

1 个答案: