オブジェクトと文字列の間の変換

<script src="../js/angular.min.js" type="text/javascript"         
    charset="utf-8">script>
    <script type="text/javascript">
        var json = {
            "name":"jack",
            "age":20
        }
        var arr = [];
//      angular    value key
        angular.forEach(json,function(val,key){
            this.push(val + ':' +key);
             
        },arr);
        console.log(arr)
script>