Javascript array conversions

Question

I have a function (that I can't change) that queries data from a database and returns it in a variable that shows as the following format if I display it as text:

var outputdata=
    [
        { itemA: 'M0929',  itemDate: new Date(1950,03-1,25,0,0,0,0),  itemID: 'JDR12' },
        { itemA: 'X0121',  itemDate: new Date(1983,07-1,07,8,0,0,0),  itemID: 'RPN50' },
        { itemA: 'U0229',  itemDate: new Date(1942,09-1,07,8,0,0,0),  itemID: 'CRG98' },
    ];

I need it to be converted into the following format (specific date formatting doesn't matter) for use by another function (that I also can't change).

var inputdata=[
        [
            "M0929",
            "1950-03-25",
            "JDR12"
        ],
        [
            "X0121",
            "1983-07-07",
            "RPN50"
        ],
        [
            "U0229",
            "1942-09-07",
            "CRG98"
        ]
    ];

Could someone offer some assistance... I don't really understand javascript arrays and I'm really after a function to do the conversion.

Answer 1

You're probably going to have to write it yourself, for example:

function pad (what)
{
    return what < 10 ? '0'+what : String(what);
}
function transformData (data)
{
    var result = [];
    for (var i=0;i<data.length;++i)
    {
        var date = data[i]['itemDate'];
        result.push([
            data[i]['itemA'],
            date.getFullYear()+'-'+pad(date.getMonth())+'-'+pad(date.getDate()),
            data[i]['itemID']
        ]);
    }
    return result;
}

var outputdata=
    [
        { itemA: 'M0929',  itemDate: new Date(1950,03-1,25,0,0,0,0),  itemID: 'JDR12' },
        { itemA: 'X0121',  itemDate: new Date(1983,07-1,07,8,0,0,0),  itemID: 'RPN50' },
        { itemA: 'U0229',  itemDate: new Date(1942,09-1,07,8,0,0,0),  itemID: 'CRG98' },
    ];

var result = transformData(outputdata);

alert(result.join("\n"));

Now, the things to be aware of are the nature of UTC dates. More details can be found here http://www.w3schools.com/jsref/jsref_obj_date.asp. Also, I highly recommend reading more about Javascript in general.

Answer 2

function convert(outputdata){
  var arr = [];
 for(var i = 0; i<outputdata.length; i++){
    var output = outputdata[i];
    var temp = [output.itemA, output.itemDate, output.itemID];
    arr[i] = temp;
 } 
 return arr;
}

Edited: initialized arr.

Answer 3

Not a full response, because this smells like homework (and if it is, you should tag it as such). So hints first:

• You can make an array by writing something like `[ 7, 9*7, "ho" ]
• You can get at properties with dot notation like obj.itemA