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JavaScript

var testjson1 = {
"Testvals": 
 [{"test1key": null, "test2key": 10, "test3key": "Test3val", "test4key": "Test4val", "test5key": [0, 1]}
], 
 "test": {"test1key": true, "test2key": 1.5, "test3key": "Test1"}, "test4key": "Test2", "test5key": "Test3", "test6key": "Test4"
}

var testjson2 = {"test": {"test1key": true, "test2key": 1.5, "test3key": "test3val"}, "test4key": "test4val", "test5key": "test5val", "test6key": "test6val"}

var finaljsonresult = $.extend(testjson1, testjson2);
console.log(JSON.stringify(finaljsonresult));//giving [object Object]
//alert(JSON.stringify(testjson1.concat(testjson2)));//if i try this, it is giving error like: VM96:56 Uncaught TypeError: testjson1.concat is not a function on my console.

//but I need to combine/merge those two json objects so that I can get only one final json object like: {"Testvals":  [{"test1key": null, "test2key": 10, "test3key": "Test3val", "test4key": "Test4val", "test5key": [0, 1]}],"test": {"test1key": true, "test2key": 1.5, "test3key": "Test1"}, "test4key": "Test2", "test5key": "Test3", "test6key": "Test4"}