How to transpose a javascript object into a key/value array

Using map function

var data = { firstName: 'John', lastName: 'Doe', email: '[email protected]' };

var result = Object.keys(data).map(key => ({ key, value: data[key] }));

console.log(result);
    

You can just iterate over the object's properties and create a new object for each of them.

var data = { firstName: 'John', lastName: 'Doe', email: '[email protected]' };
var result = [];

for(var key in data)
{
    if(data.hasOwnProperty(key))
    {
        result.push({
            key: key,
            value: data[key]
        });
    }
}

var data = { firstName: 'John', lastName: 'Doe', email: '[email protected]' }
var output = Object.entries(data).map(([key, value]) => ({key,value}));

console.log(output);

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