Convert object's properties and values to array of key value pairs

You're probably looking for something along the lines of

var obj = {value1: 'prop1', value2: 'prop2', value3: 'prop3'};
var arr = [];
for (var key in obj) {
    if (obj.hasOwnProperty(key)) {
        arr.push(key + '=' + obj[key]);
    }
};
var result = arr.join(',');
alert(result);

Notice that it will work fine if your values are strings; if they're complex objects then you'll need to add more code.

Or you can just use jQuery.param, which does what you want, even for complex types (although it uses the & character as the separator, instead of the comma.

In ES6 you can use Object.entries({object1:1,object2:2});. The result is: [["object1",1],["object2",2]]

var array = [];
for (k in o)
{
    if (o.hasOwnProperty(k))
    {
        array.push(k+"="+o[k]);
    }
}

You can then join the array for your final string.