iOS NET Error Code

see NSURLError.h Define

NSURLErrorUnknown =             -,
NSURLErrorCancelled =           -,
NSURLErrorBadURL =              -,
NSURLErrorTimedOut =            -,
NSURLErrorUnsupportedURL =          -,
NSURLErrorCannotFindHost =          -,
NSURLErrorCannotConnectToHost =         -,
NSURLErrorNetworkConnectionLost =       -,
NSURLErrorDNSLookupFailed =         -,
NSURLErrorHTTPTooManyRedirects =        -,
NSURLErrorResourceUnavailable =         -,
NSURLErrorNotConnectedToInternet =      -,
NSURLErrorRedirectToNonExistentLocation =   -,
NSURLErrorBadServerResponse =       -,
NSURLErrorUserCancelledAuthentication =     -,
NSURLErrorUserAuthenticationRequired =  -,
NSURLErrorZeroByteResource =        -,
NSURLErrorCannotDecodeRawData =             -,
NSURLErrorCannotDecodeContentData =         -,
NSURLErrorCannotParseResponse =             -,
NSURLErrorAppTransportSecurityRequiresSecureConnection NS_ENUM_AVAILABLE(10_11, 9_0) = -,
NSURLErrorFileDoesNotExist =        -,
NSURLErrorFileIsDirectory =         -,
NSURLErrorNoPermissionsToReadFile =     -,
NSURLErrorDataLengthExceedsMaximum NS_ENUM_AVAILABLE(10_5, 2_0) =   -,

// SSL errors
NSURLErrorSecureConnectionFailed =      -,
NSURLErrorServerCertificateHasBadDate =     -,
NSURLErrorServerCertificateUntrusted =  -,
NSURLErrorServerCertificateHasUnknownRoot = -,
NSURLErrorServerCertificateNotYetValid =    -,
NSURLErrorClientCertificateRejected =   -,
NSURLErrorClientCertificateRequired =   -,
NSURLErrorCannotLoadFromNetwork =       -,

// Download and file I/O errors
NSURLErrorCannotCreateFile =        -,
NSURLErrorCannotOpenFile =          -,
NSURLErrorCannotCloseFile =         -,
NSURLErrorCannotWriteToFile =       -,
NSURLErrorCannotRemoveFile =        -,
NSURLErrorCannotMoveFile =          -,
NSURLErrorDownloadDecodingFailedMidStream = -,
NSURLErrorDownloadDecodingFailedToComplete =-,

NSURLErrorInternationalRoamingOff NS_ENUM_AVAILABLE(10_7, 3_0) =         -,
NSURLErrorCallIsActive NS_ENUM_AVAILABLE(10_7, 3_0) =                    -,
NSURLErrorDataNotAllowed NS_ENUM_AVAILABLE(10_7, 3_0) =                  -,
NSURLErrorRequestBodyStreamExhausted NS_ENUM_AVAILABLE(10_7, 3_0) =      -,

NSURLErrorBackgroundSessionRequiresSharedContainer NS_ENUM_AVAILABLE(10_10, 8_0) = -,
NSURLErrorBackgroundSessionInUseByAnotherProcess NS_ENUM_AVAILABLE(10_10, 8_0) = -,
NSURLErrorBackgroundSessionWasDisconnected NS_ENUM_AVAILABLE(10_10, 8_0)= -,

参考链接：

https://stackoverflow.com/questions/6778167/undocumented-nsurlerrordomain-error-codes-1001-1003-and-1004-using-storeki