奇怪的jQuery多类型锯齿状数组

Question

Please refer to this:

http://jsfiddle.net/MasterOfKitties/v7xbu/7/

/*This is the desired behavior*/
/*var A = [1, 2, 3]*/
/*var B = "hello", [1, 2, 3],
         "hello", [2, 3, 2],
         "hello", [1, 5, 1]]*/

var A = new Array();
var B = new Array();

function fnMakeArray()
    {
     var strTemp;
     var arrTemp = new Array();
     strTemp = parseInt(window.prompt("Enter a number until you hit cancel",""));  


  while (strTemp>0)
      {
         arrTemp.push(strTemp);   
         strTemp =  parseInt(window.prompt("Enter a number until you hit cancel",""));
      }  
        A[0] = "hello";
        A[1] = arrTemp;
        alert(A);
    }


function fnReplicateArray()
    {
        B.push(A); 
        fnDisBArray();
        alert(B);

    }

function fnDisBArray()
{
    var strTemp;
 for(var x = 0; x<B.length;x++)
     {
         strTemp += "<P>" + B[x] + "</p>"

     }
     document.getElementById('parse').innerHTML = strTemp ;  


}

For some reason, when attempting to display the B array, it puts out undefined. Furthermore, it does not seem to increment the jagged array correctly, as the b[0] element begins to radically change even though the b[1] or b[2] element is being arranged.

Any assistance? What's going on?

Answer 1

you have to initialize strTemp with a value.

like

var strTemp = "";

instead of

var strTemp;

in your case.

when the line

 strTemp += "<P>" + B[x] + "</p>"

is executing for the first time strTemp is undefined so its converted to string as undefined and gets appended in the begining

see the working fiddle

Answer 2

Your function does not "replicate"/copy the A array, it just pushes a reference to A into B. I believe you want:

B = A.slice(0); 

Now, you seem to have another problem: if you enter eg 10 and 11 into the prompts, you get this array at the end:

[
    "hello",
    [
        10,
        11
    ]
]

I suspect that's not really what you're looking for. Could you please explain what you're really trying to accomplish?