Question

请参阅以下html

<div class="testclass" style="top:30px;">msg1</div>
<div class="testclass" style="top:60px;">msg2</div>
<div class="testclass" style="top:80px;">msg3</div>
<div class="testclass" style="top:100px;">msg4</div>
<div class="testclass" style="top:200px;">msg5</div>

选择小于623的随机值，并且该随机值不在元素的停止样式中，即不在30,60,80,100,200中。但这些值会发生变化。并且该随机值需要从最高值至少多30个。这该怎么做

Answer 1

<!DOCTYPE html>
<html>
<head>
  <title>hello</title>
</head>
<body>

  <div class="testclass" style="top:30px;">msg1</div>
  <div class="testclass" style="top:60px;">msg2</div>
  <div class="testclass" style="top:80px;">msg3</div>
  <div class="testclass" style="top:100px;">msg4</div>
  <div class="testclass" style="top:200px;">msg5</div>

  <button>Generate Random number</button>

  <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>

  <script>

    function isNotValid(arr, val){ // checks if the random value is valid
      var check = false;

      $.each(arr, function(v){
            if(val < (v+30)){
              check = true;
              return;
            }
      });

      return check;
    }    

    function getRandomNum(max, min) { // getting random value
      return parseInt(Math.random() * (max - min) + min);
    }

    $(document).ready(function(){
        $("button").click(function(){
            var topValues = [];

            $(".testclass").each(function(){ // stores [30, 60, 80, 100, 200] in topValues variable
               topValues.push(parseInt($(this).css('top')));
            });

            var randomValue = 0;

            do{
                 randomValue = getRandomNum(623, 0); // max, min for fetching random value. You can pass the smallest topValues as min to optimize the process
            } while(isNotValid(topValues, randomValue)); // fetch random value until its not valid


            alert(randomValue); // alert random value
        });
    });

  </script>

</body>

以上是完整的工作代码，但它可以更加精致。我相信这会对你有所帮助:)。

根据Jquery中的条件选择随机值

1 个答案: