"IOS" File upload little note

iOS with the system-provided API can be implemented to achieve file upload and download, respectively, there are two ways. nsurlconnection and nsurlsession.

Where Nsurlconnection is a long-used way, nsurlsession is a new way out.

First, Post mode upload

The post submission information is used by default:*Content-type: application/x-www-form-urlencoded.*when entering Chinese,PostAutomatic escape mode(Automatic in Apple).
most websites in the country use this approachUploading Files(support for binary files)*Content-type:Multipart/form-data(Uploading Files)*will limit the size of the uploaded fileis generally2Mor smaller.

Uploading in Apple is a hassle. You need to stitch up the required string format for uploading before uploading. (Plus head)

Other platforms do a good bit of the possible encapsulation, do not need to stitch their own string format. So it's rarely uploaded in this way in iOS.

Example code:

#import "XNUploadFile.h" #define Ktimeout 5.0f@implementation xnuploadfile/** delimited string */static nsstring *boundarystr = @ "--    /** this upload flag string */static nsstring *randomidstr;/** Upload (PHP) script, receive file field */static nsstring *uploadid;-(instancetype) init{    self = [super init];        if (self) {/** This upload marked String */Randomidstr = @ "Itcastupload";    /** Upload (PHP) script, receive file field *//can consult the company's website development Programmer//or use Firebug to track and debug Uploadid = @ "UploadFile"; } return self;}  #pragma the mark-member method. Complete upload with nsurlsession-(void) UploadFile: (NSString *) path filename: (NSString *) filename completion: (void (^) (NSString * String) completion{//1. URL Hint: Really responsible for file upload is PHP file, not html file nsurl *url = [Nsurl urlwithstring:@ "http://localhost/new/        Post/upload.php "]; 2.        Request Nsurlrequest *request = [self Requestforuploadurl:url uploadfilename:filename localfilepath:path]; 3.        Session (Reply)//Global network reply, in order to facilitate the use of network services programmers nsurlsession *session = [Nsurlsession sharedsession]; 4. The task of data task-----/** urlsession, which is initiated by the reply, is done by default on other threads, and is asynchronous by default */[Session Datataskwithrequest:request Completionhand ler:^ (NSData *data, Nsurlresponse *response, Nserror *error) {id result = [nsjsonserialization jsonobjectw                Ithdata:data options:0 Error:null];                NSLog (@ "%@%@", result, [Nsthread CurrentThread]);            Dispatch_async (Dispatch_get_main_queue (), ^{if (completion) {completion (@ "Download complete");    }        });        }] [resume]; Nsurlsessiondatatask *task = [Session datataskwithrequest:request completionhandler:^ (NSData *data, NSURLResponse *r Esponse, Nserror *error) {////ID result = [nsjsonserialization jsonobjectwithdata:data options:0 Error:nul    L];    NSLog (@ "%@%@", result, [Nsthread CurrentThread]); Dispatch_async (Dispatch_get_main_queue (), ^{//if (completion) {//Compl    Etion (@ "Download complete"); //            }    //        });    //    }]; //5. Start a task//[task resume];} #pragma mark-Private method: spelling string/** stitching top String */-(NSString *) Topstringwithmimetype: (NSString *) MimeType uploadfile: (NSString *) up        loadfile{nsmutablestring *STRM = [nsmutablestring string];    [StrM appendformat:@ "%@%@\n", Boundarystr, Randomidstr];    [StrM appendformat:@ "content-disposition:form-data; name=\"%@\ "; filename=\"%@\ "\ n", Uploadid, UploadFile];        [StrM appendformat:@ "Content-type:%@\n\n", MimeType];    NSLog (@ "Top string:%@", StrM); return [StrM copy];}        /** stitching the bottom string */-(NSString *) bottomstring{nsmutablestring *STRM = [nsmutablestring string];    [StrM appendformat:@ "%@%@\n", Boundarystr, Randomidstr];    [StrM appendstring:@ "content-disposition:form-data; name=\" submit\ "\ n"];    [StrM appendstring:@ "submit\n"];        [StrM appendformat:@ "%@%@--\n", Boundarystr, Randomidstr];    NSLog (@ "bottom string:%@", StrM); return [StrM copy];} /** Specifies the mimetype */-(NSString *) of the full path file MimetypewithfilepAth: (NSString *) filepath{//1. Determine if the file exists if (![    [Nsfilemanager Defaultmanager] Fileexistsatpath:filepath]) {return nil; }//2.    Use the HTTP head method to get the uploaded file information nsurl *url = [Nsurl Fileurlwithpath:filepath];        Nsmutableurlrequest *request = [Nsmutableurlrequest Requestwithurl:url]; 3.    Call the synchronous method to get the file's mimetype nsurlresponse *response = nil;        [Nsurlconnection sendsynchronousrequest:request returningresponse:&response Error:NULL]; return response. MIMEType;} /** upload file network request */-(Nsurlrequest *) Requestforuploadurl: (nsurl *) URL uploadfilename: (NSString *) FileName Localfilepath: (    NSString *) filepath{//0. Get the uploaded file mimeType nsstring *mimetype = [self mimetypewithfilepath:filepath];        if (!mimetype) return nil; 1.    Stitching the data body to be uploaded nsmutabledata *datam = [Nsmutabledata data]; [Datam appenddata:[[self Topstringwithmimetype:mimetype Uploadfile:filename] datausingencoding:    Nsutf8stringencoding]]; Stitching the binary data of the uploaded file itself [Datam appenddata:[nsdata DatawitHcontentsoffile:filepath]];        [Datam appenddata:[[self bottomstring] datausingencoding:nsutf8stringencoding]; 2.    Set request Nsmutableurlrequest *requestm = [nsmutableurlrequest requestwithurl:url cachepolicy:0 TimeoutInterval:kTimeOut];    1> Set HTTP request mode Requestm.httpmethod = @ "POST";    2> setting Data Body requestm.httpbody = Datam; 3> Specifies content-type nsstring *typestr = [NSString stringwithformat:@ "multipart/form-data; boundary=%@", RandomIDStr    ];    [Requestm setvalue:typestr forhttpheaderfield:@ "Content-type"];    4> Specifies the data length nsstring *lengthstr = [NSString stringwithformat:@ "%@" @ ([Datam length])];        [Requestm setvalue:lengthstr forhttpheaderfield:@ "Content-length"]; return [requestm copy];}

Note:POSTwhen uploading,is aduplicate names are not allowedof the.(otherwise error)

Second, put the way to upload

Sessionin theUploadmethod can only be used forPUTUpload,cannot be used forPOSTUpload.

withPUTWay to uploadBenefits:(Authentication Required)*not likePOSTsame,spell a bunch of strings.*directlyBase64encode a bit of authentication, Sessionof theUploadOne call on the line..*no file size limit.*Instant MessagingIt 's a lot of use..(Send picture/Send Voice)

-(void) putfile{//1. The last URL to upload is the file name to be uploaded nsurl *url = [Nsurl urlwithstring:@ "HTTP://LOCALHOST/UPLOADS/ABCD"];//ABCD is File name//2.    Request Nsmutableurlrequest *request = [Nsmutableurlrequest Requestwithurl:url]; Request. HttpMethod = @ "PUT";//Request.        HttpMethod = @ "DELETE";    Set up user authorization//BASE64 encoding: A "most commonly used network encoding method" for encoding strings and binary data, which converts binary data to strings!    is the underlying algorithm of many cryptographic algorithms//BASE64 support anti-coding, is a bidirectional encoding scheme nsstring *AUTHSTR = @ "admin:123";    NSString *authbase64 = [NSString stringwithformat:@ "Basic%@", [self base64encode:authstr]];        [Request Setvalue:authbase64 forhttpheaderfield:@ "Authorization"]; 3.        Urlsession nsurlsession *session = [Nsurlsession sharedsession]; 4.    Task initiated by session nsurl *localurl = [[NSBundle mainbundle] urlforresource:@ "001.png" withextension:nil]; [[Session Uploadtaskwithrequest:request Fromfile:localurl completionhandler:^ (NSData *data, NSURLResponse *response, Nserror *error) {nsstring *result = [[NSSTring Alloc] Initwithdata:data encoding:nsutf8stringencoding];    NSLog (@ "Sesult--->%@%@", result, [Nsthread CurrentThread]); }] [resume];} -(NSString *) Base64Encode: (NSString *) str{//1. Converting strings to binary data nsdata *data = [Str datausingencoding:nsutf8stringenc        Oding]; 2.        The binary data is base64 encoded nsstring *result = [data base64encodedstringwithoptions:0];        NSLog (@ "base464-->%@", result); return result;}

The Put method corresponds to delete, which deletes the file uploaded by the put method.

Tips:session Use note

*Network Session,convenient for programmers to use Web services.*as:can get the current upload file progress.*nsurlsessionthe Task, by default, allAsynchronousof the.(working in other threads)*Taskis bySessionInitiated by.*Note Network requests are handled with error.*SessionThe default is pending,need toResumeto start ..

Reprint Please specify source:http://blog.csdn.net/xn4545945