How to loop through a JSON object with typescript (Angular2)

ECMAScript 6 introduced the let statement. You can use it in a for statement.

var ids:string = [];

for(let result of this.results){
   ids.push(result.Id);
}

Assuming your json object from your GET request looks like the one you posted above simply do:

let list: string[] = [];

json.Results.forEach(element => {
    list.push(element.Id);
});

Or am I missing something that prevents you from doing it this way?