我试图将详细信息发布到Server ..我得到了responseCode“：”400

Question

JSON数据：

{
    "name":"NAME",
    "mobile":"MOBILE NUMER",
    "email":”EMAIL_ID” 
}

我尝试了以下代码：

var request = URLRequest(url: URL(string: url_to_request)!)
request.httpMethod = "POST"

//  let postString: [String: AnyObject] = ["name":name,"mobile":mobile,"email":email]

let postString:String = "name:\(name)&mobile:\(mobile)&email:\(email)"

request.httpBody = postString.data(using: .utf8)
let task = URLSession.shared.dataTask(with: request) { data, response, error in
    guard let data = data, error == nil else {                                                 // check for fundamental networking error
        print("error=\(error)")
        return
    }

    if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {           // check for http errors
        print("statusCode should be 200, but is \(httpStatus.statusCode)")
        print("response = \(response)")
    }

    let responseString = String(data: data, encoding: .utf8)
    print("responseString = \(responseString!)")
}
task.resume()

我得到了以下结果：

responseString = {"responseCode":"400"}

我正在使用Swift 3和Xcode 8。