ios - AFNetworking 从响应中删除字符

Question

我正在使用 AFNetworking 来使用基本身份验证调用 Web 服务。问题是我得到了

FAILURE: Error Domain=NSCocoaErrorDomain Code=3840 "JSON text did not start with array or object and option to allow fragments not set." UserInfo={NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.}

当我允许片段时，我得到

Invalid value around character 0

我与我们的 Web 开发人员进行了交谈，他出于某种原因在 JSON 响应前添加了“//”前缀，因此我需要在使用 JSON 之前修剪这些内容。我的问题是，我不确定如何访问响应来修剪它并使用它，因为代码立即转到故障 block 。

let manager = AFHTTPSessionManager(baseURL: URL(string: "http://mydev1.kyfb.com/remote/appinfo.cfc?method=GetMemberInfo"))
            manager.requestSerializer.setAuthorizationHeaderFieldWithUsername(emailTextField.text!, password: passwordTextField.text!)
            // manager.responseSerializer = AFJSONResponseSerializer(readingOptions: .allowFragments)
            // manager.responseSerializer = AFHTTPResponseSerializer()
            manager.post("", parameters: nil, progress: nil, success: {
                (task, responseObject) -> Void in
                // TODO: If error message returned in JSON response, display error
                // else login was successful. Save user info to User object and push AccountTableViewController
                print("RESPONSE OBJECT: \(responseObject!)")
                let responseJSON = responseObject as? [String: AnyObject]
                print("RESPONSE JSON: \(responseJSON)")
                if responseJSON!["MEMBERSHIPNUMBER"] != nil {

                }

            }, failure: {
                (operation, error) -> Void in
                // TODO: Display error
                print("FAILURE: \(error)")
            })
        }

Answer 1

如果您将 responseSerializer 设置为 AFHTTPResponseSerializer，其中:manager.responseSerializer = AFHTTPResponseSerializer()，则 responseObject 应该是一个 (NS)Data 对象。

要做什么:
获取 "//" 的值(我们称之为 prefixData)。
检查 responseObject 前缀中是否有它。
如果需要，请删除。

let prefixData = "//".data(using: .utf8)!        
//OR let prefixData = Data(bytes: [0x2F, 0x2F])

let responsePrefix = responseObject.subdata(in: Range(0..<2))
if responsePrefix == prefixData {
    let jsonData = responseObject.subdata(in: Range(2..<responseObject.count))
    //You got your JSON to serialize with Codable or JSONSerialization
}

出于逻辑原因，使用强制展开和静默尝试(尝试？)(不要这样做)的示例代码:

let prefixData = "//".data(using: .utf8)!
print("prefixData from String: \(prefixData as NSData)")

let prefixData2 = Data(bytes: [0x2F, 0x2F])
print("prefixData from Bytes: \(prefixData2 as NSData)")

if prefixData == prefixData2 {
    print("prefixData == prefixData2, use the one you want")
}

let responseObject = "//{\"key\":\"value\"}".data(using: .utf8)!
print("responseObject: \(responseObject as NSData)")

let responsePrefix = responseObject.subdata(in: Range(0..<2))
if responsePrefix == prefixData {
    let jsonData = responseObject.subdata(in: Range(2..<responseObject.count))
    print("jsonData: \(jsonData as NSData)")
    let json = try? JSONSerialization.jsonObject(with: jsonData, options: [])
    print("json: \(json!)")
    let jsonString = String(data: jsonData, encoding: .utf8)
    print("jsonString: \(jsonString!)")
} 

输出:

$>prefixData from String: <2f2f>
$>prefixData from Bytes: <2f2f>
$>prefixData == prefixData2, use the one you want
$>responseObject: <2f2f7b22 6b657922 3a227661 6c756522 7d>
$>jsonData: <7b226b65 79223a22 76616c75 65227d>
$>json: Optional({
key = value;
})
$>jsonString: {"key":"value"}