How to add items in json data object while sending to DB

 i need to upload abulk data of jsonobject.In service .ts i need to add extraa 4 more values to that object.In body ineed to get this values to save how can i append these 4 values to body

 

 my service.ts

************** 

SaveData(uploaddata: any) {

 

//this four data i need to add to the object "body"

// ID":ID,

// "CreatedBy": "",

// "CreatedOn": "",

// "UpdatedBy": "",

// "UpdatedOn": ""

/

let body = JSON.stringify(uploaddata)

console.log(body)

let headers = new Headers({

'Content-Type':

'application/json; charset=utf-8'

});

let options = new RequestOptions({ headers: headers });

return this._http.post(this.Savecsv, body, options)

.map(res => res.json())

.catch(this.handleError);

}