Question

需要一些帮助才能完成使用成功函数的Javascript程序。我找不到用变量替换return语句的方法，所以我可以在第二个函数中使用varable。

程序使用语句findArrayparts(myArray1, myArray2)来使函数findArrayparts(myArray1, myArray2)生成一个随机整数，该整数小于其中一个数组（等长）的数组长度。

然后在函数findArrayparts(myArray1, myArray2)中使用此随机整数来计算出相应的数组元素，并将它们放入一个数组中，然后显示在一个警告框中。

<SCRIPT SRC = glossary.js></SCRIPT>
<SCRIPT language = "JavaScript">
var myVar1;
var myVar2;
var myVar3;

var myArray1 = ['red', 'orange', 'green', 'blue', 'yellow'];
var myArray2 = ['tomatoe', 'orange', 'apples', 'blueberry', 'banana'];

// generates random integer and assigns result to myVar1
function getNumberRand(aNum)
   {
     //return Math.floor(Math.random() * aNum); 
     myVar1 =  Math.floor(Math.random() * aNum); 
   }

   function findArrayparts(myArray1, myArray2)    
    {   
// calls getNumberRand function         
      getNumberRand(myArray1.length); 

      // works out characters at same index in both arrays
      myVar2 = (myArray1(myVar1));
      myVar3 = (myArray2(myVar1)); 

      // new array to hold output
      outputArray = new Array(myVar2, myVar3);

        // display output
      outputArray.join();
        alert(outputArray); 
    }    

// Calls findArrayparts function        
    findArrayparts(myArray1, myArray2);


</SCRIPT>


</HEAD>
<BODY>
</BODY>
</HTML>

Answer 1

DEMO： http://jsfiddle.net/PjtxY/

var myArray1 = ['red', 'orange', 'green', 'blue', 'yellow'];
var myArray2 = ['tomatoe', 'orange', 'apples', 'blueberry', 'banana'];


function getNumberRand(aNum) {
    return Math.floor(Math.random() * aNum); 
}

function findArrayparts(myArray1, myArray2) {

        // Store return value in local variable   
    var random_num = getNumberRand(myArray1.length);

       // Use [] square brackets to get array member
    var myVar2 = myArray1[ random_num ];
    var myVar3 = myArray2[ random_num ];

       // Store new Array in local variable.
    var outputArray = new Array(myVar2, myVar3);

       // Store joined result in a variable
    var result = outputArray.join();

       // Alert the result
    alert( result );
}

findArrayparts(myArray1, myArray2);

Answer 2

你在注释掉的行中有它。只需返回值：

function getNumberRand(aNum)
{
    return Math.floor(Math.random() * aNum); 
}

Answer 3

您在评论之前已经getNumberRand了。您想要返回随机数：

function getNumberRand(aNum)
{
 return Math.floor(Math.random() * aNum); 

}

然后，当您想要稍后使用该函数的返回时，只需将结果赋值给变量：

function findArrayparts(myArray1, myArray2)    
{   
// calls getNumberRand function         
  var myVar1 = getNumberRand(myArray1.length); 

  // works out characters at same index in both arrays
  myVar2 = (myArray1(myVar1));
  myVar3 = (myArray2(myVar1)); 

  ...
}

Answer 4

为什么使用全局变量myVar1，myVar2，myVar3？使用return从函数中获取值。

这是你想要实现的目标：

<script type="text/javascript">

var myArray1 = ['red', 'orange', 'green', 'blue', 'yellow'];
var myArray2 = ['tomato', 'orange', 'apples', 'blueberry', 'banana'];

function getNumberRand(aNum)
{
    return Math.floor(Math.random() * aNum); 
}

function findArrayparts(myArray1, myArray2)    
{   
    var index = getNumberRand(myArray1.length); 
    alert(outputArraymyArray1[index] + ', ' + myArray2[index]);
}    

findArrayparts(myArray1, myArray2);


</script>

返回数组的函数

4 个答案: