Error
最近在修改一個網(wǎng)絡(luò)請求的
bug時，由于一直請求失敗调鬓，所以在尋找具體失敗原因的時候衰絮，了解了一下請求失敗的錯誤返回NSError，發(fā)現(xiàn)原來可以通過NSError中的code屬性來判斷請求失敗的具體原因注暗，就在這里記錄順便分享一下。
判斷方法
通過判斷 NSError 中的 code 錯誤碼屬性墓猎，可以判斷具體失敗原因捆昏，下面以 NSURLErrorTimedOut 請求超時為例。
/* 開始請求 */
[manager POST:url parameters:parameters progress:nil success:^(NSURLSessionDataTask * _Nonnull task, id _Nullable responseObject) {
NSLog(@"網(wǎng)絡(luò)請求成功毙沾！");
} failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
NSLog(@"網(wǎng)絡(luò)請求失斊贰！");
if (error.code == NSURLErrorTimedOut) {
NSLog(@"網(wǎng)絡(luò)請求超時左胞！");
}
}];
錯誤碼
這里給出蘋果提供的所有網(wǎng)絡(luò)請求的錯誤碼寇仓，可以根據(jù)不同錯誤碼來給出不同的錯誤提示以及給出相應(yīng)的操作，想具體了解每個錯誤碼對應(yīng)什么意思可以自行查詢一下官方文檔烤宙。
/*!
@enum NSURL-related Error Codes
@abstract Constants used by NSError to indicate errors in the NSURL domain
*/
NS_ENUM(NSInteger)
{
NSURLErrorUnknown = -1,
NSURLErrorCancelled = -999,
NSURLErrorBadURL = -1000,
NSURLErrorTimedOut = -1001,
NSURLErrorUnsupportedURL = -1002,
NSURLErrorCannotFindHost = -1003,
NSURLErrorCannotConnectToHost = -1004,
NSURLErrorNetworkConnectionLost = -1005,
NSURLErrorDNSLookupFailed = -1006,
NSURLErrorHTTPTooManyRedirects = -1007,
NSURLErrorResourceUnavailable = -1008,
NSURLErrorNotConnectedToInternet = -1009,
NSURLErrorRedirectToNonExistentLocation = -1010,
NSURLErrorBadServerResponse = -1011,
NSURLErrorUserCancelledAuthentication = -1012,
NSURLErrorUserAuthenticationRequired = -1013,
NSURLErrorZeroByteResource = -1014,
NSURLErrorCannotDecodeRawData = -1015,
NSURLErrorCannotDecodeContentData = -1016,
NSURLErrorCannotParseResponse = -1017,
NSURLErrorAppTransportSecurityRequiresSecureConnection NS_ENUM_AVAILABLE(10_11, 9_0) = -1022,
NSURLErrorFileDoesNotExist = -1100,
NSURLErrorFileIsDirectory = -1101,
NSURLErrorNoPermissionsToReadFile = -1102,
NSURLErrorDataLengthExceedsMaximum NS_ENUM_AVAILABLE(10_5, 2_0) = -1103,
NSURLErrorFileOutsideSafeArea API_AVAILABLE(macosx(10.12.4), ios(10.3), watchos(3.2), tvos(10.2)) = -1104,
// SSL errors
NSURLErrorSecureConnectionFailed = -1200,
NSURLErrorServerCertificateHasBadDate = -1201,
NSURLErrorServerCertificateUntrusted = -1202,
NSURLErrorServerCertificateHasUnknownRoot = -1203,
NSURLErrorServerCertificateNotYetValid = -1204,
NSURLErrorClientCertificateRejected = -1205,
NSURLErrorClientCertificateRequired = -1206,
NSURLErrorCannotLoadFromNetwork = -2000,
// Download and file I/O errors
NSURLErrorCannotCreateFile = -3000,
NSURLErrorCannotOpenFile = -3001,
NSURLErrorCannotCloseFile = -3002,
NSURLErrorCannotWriteToFile = -3003,
NSURLErrorCannotRemoveFile = -3004,
NSURLErrorCannotMoveFile = -3005,
NSURLErrorDownloadDecodingFailedMidStream = -3006,
NSURLErrorDownloadDecodingFailedToComplete =-3007,
NSURLErrorInternationalRoamingOff NS_ENUM_AVAILABLE(10_7, 3_0) = -1018,
NSURLErrorCallIsActive NS_ENUM_AVAILABLE(10_7, 3_0) = -1019,
NSURLErrorDataNotAllowed NS_ENUM_AVAILABLE(10_7, 3_0) = -1020,
NSURLErrorRequestBodyStreamExhausted NS_ENUM_AVAILABLE(10_7, 3_0) = -1021,
NSURLErrorBackgroundSessionRequiresSharedContainer NS_ENUM_AVAILABLE(10_10, 8_0) = -995,
NSURLErrorBackgroundSessionInUseByAnotherProcess NS_ENUM_AVAILABLE(10_10, 8_0) = -996,
NSURLErrorBackgroundSessionWasDisconnected NS_ENUM_AVAILABLE(10_10, 8_0)= -997,
};
其實
NSError還有很多別的錯誤碼遍烦，這里只給出網(wǎng)絡(luò)請求相關(guān)的，其他的以后遇到了再記錄下來吧躺枕。
將來的你服猪，一定會感激現(xiàn)在拼命的自己，愿自己與讀者的開發(fā)之路無限美好拐云。
