Question

I have got three similar json objects. Now i wish to join the entire list and then sort the complete list according to one of the index. Here, goes the objects description

Object 1

[{"link":"#","prod":"Fundamentals Of Software Engineering","price":" Rs. 200 "},{"link":"##","prod":"Real-Time Systems: Theory And Practice","price":" Rs. 394 "}]

Object 2

[{"link":"#","prod":"Fundamentals Of Software Engineering","price":" Rs. 200 "},{"link":"##","prod":"Real-Time Systems: Theory And Practice","price":" Rs. 394 "}] 

Object 3

[{"link":"#","prod":"Fundamentals Of Software Engineering","price":" Rs. 200 "},{"link":"##","prod":"Real-Time Systems: Theory And Practice","price":" Rs. 394 "}] 

Once, I join all of them , I wish to sort the complete array (new one) w.r.t to price index.

Any hint for this will be appreciated.
thanks 🙂

Answer 1

if Object1 , Object2 and Object3 are JSON strings convert it to Javascript objects using eval function.

Then merge them using concat method.
http://www.w3schools.com/jsref/jsref_concat_array.asp

var mergedArray = arr1.concat(arr2, arr3);

Then sort using sort method in Javascript Array.
ref : http://www.w3schools.com/jsref/jsref_sort.asp
ref: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/sort

var sorted = mergedArray.sort(function(a, b){

    // This function is used by sort method for sorting process
    // This function gets called with parameters a,b which are the elements in array (here product objects from your JSON)
    // if this function returns value < 0 a is placed before b
    // if this function returns 0 nothing is changed
    // if this function returns value > 0 b is placed before a
    // a.price.replace("Rs.", "") removes Rs. from price string. so "Rs. 200" becomes 200
    // parseFloat(a.price.replace("Rs.", "")) makes it number.  "200" becomes 200. "200.50" becomes 200.5
    // priceA - priceB returns -ve value if priceA < priceB, 0 if priceA = priceB, +ve value if priceA > priceB.

    var priceA = parseFloat(a.price.replace("Rs.", ""));
    var priceB = parseFloat(b.price.replace("Rs.", ""));
    return priceA - priceB;



});

Use return priceB - priceA; for descending order.
jsfiddle : http://jsfiddle.net/diode/FzzHz/

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