iOS development--Network Swift chapter &nsurlsession loading data, downloading, uploading files

Nsurlsession loading data, downloading, uploading files
The Nsurlsession class supports three types of tasks: loading data, downloading, and uploading. The following examples are presented below.1, loading data using the database taskCreated using the global Sharedsession () and Datataskwithrequest methods.

1 func sessionloaddata () {2     //Create a Nsurl object3Let urlstring:string="http://hangge.com"4var url:nsurl! = Nsurl (string: urlstring)5     //Create Request Object6var request:nsurlrequest =nsurlrequest (Url:url)7      8Let session =nsurlsession.sharedsession ()9    Tenvar datatask =session.datataskwithrequest (Request, OneCompletionhandler: {(data:nsdata!, response:nsurlresponse!, error:nserror!), Voidinch A             ifError! =nil{ -println (error?). Code) -println (error?). Description) the}Else{ -var str = nsstring (data:data!, encoding:nsutf8stringencoding) - println (str) -             } +}) asNsurlsessiontask -       +     //To start a task by using the Resume method A Datatask.resume () at}

2. Use download task to download the file(1) No need to get progressUse the Sharedsession () and Downloadtaskwithrequest methods to

1 func sessionsimpledownload () {2     //3var url = nsurl (string:"Http://hangge.com/blog/images/logo.png")4     //Request5var request:nsurlrequest = nsurlrequest (url:url!)6      7Let session =nsurlsession.sharedsession ()8      9     //Download TaskTenvar downloadtask =session.downloadtaskwithrequest (Request, OneCompletionhandler: {(location:nsurl!, response:nsurlresponse!, error:nserror!), Voidinch A             //Output download File The original storage directory -println"location:\ (location)") -             //Location Conversion thevar Locationpath =Location.path -             //Copy to User directory -Let documnets:string = nshomedirectory () +"/documents/1.png" -             //creating a File Manager +var Filemanager:nsfilemanager =Nsfilemanager.defaultmanager () -Filemanager.moveitematpath (locationpath!, Topath:documnets, Error:nil) +println"new Location:\ (documnets)") A     }) at       -     //To start a task by using the Resume method - Downloadtask.resume () -}

(2) real-time access to progress
You need to use a custom Nsurlsession object and a Downloadtaskwithrequest method

1 Import UIKit2  3 classViewcontroller:uiviewcontroller, nsurlsessiondownloaddelegate {4  5     Overridefunc viewdidload () {6 super.viewdidload ()7          8 sessionseniordownload ()9     }Ten       One     //Download File A func sessionseniordownload () { -         // -var url = nsurl (string:"Http://hangge.com/blog/images/logo.png") the         //Request -var request:nsurlrequest = nsurlrequest (url:url!) -           -Let session = Currentsession () asnsurlsession +           -         //Download Task +var downloadtask =session.downloadtaskwithrequest (Request) A           at         //To start a task by using the Resume method - Downloadtask.resume () -     } -       -     //Create a download mode -Func currentsession ()nsurlsession{ invar predicate:dispatch_once_t =0 -var currentsession:nsurlsession? =Nil to          +Dispatch_once (&predicate, { -var config =nsurlsessionconfiguration.defaultsessionconfiguration () theCurrentsession = Nsurlsession (Configuration:config,Delegate: Self, Delegatequeue:nil) *         }) $         returncurrentsession!Panax Notoginseng     } -       the     //Download Agent method, download end + func urlsession (session:nsurlsession, Downloadtask:nsurlsessiondownloadtask, A Didfinishdownloadingtourl Location:nsurl) { the         //End of Download +println"End of Download") -           $         //Output download File The original storage directory $println"location:\ (location)") -         //Location Conversion -var Locationpath =Location.path the         //Copy to User directory -Let documnets:string = nshomedirectory () +"/documents/1.png"Wuyi         //creating a File Manager thevar Filemanager:nsfilemanager =Nsfilemanager.defaultmanager () -Filemanager.moveitematpath (locationpath!, Topath:documnets, Error:nil) Wuprintln"new Location:\ (documnets)") -     } About       $     //Download Agent method, listen to download progress - func urlsession (session:nsurlsession, Downloadtask:nsurlsessiondownloadtask, - Didwritedata Byteswritten:int64, Totalbyteswritten:int64, Totalbytesexpectedtowrite:int64) { -         //Get Progress Avar written:cgfloat =(CGFloat) (Totalbyteswritten) +var total:cgfloat =(CGFloat) (totalbytesexpectedtowrite) thevar pro:cgfloat = written/ Total -println"Download progress: \ (PRO)") $     } the       the     //Download Agent method, download offset the func urlsession (session:nsurlsession, Downloadtask:nsurlsessiondownloadtask, the didresumeatoffset Fileoffset:int64, Expectedtotalbytes:int64) { -         //download offset, mainly used to pause the resume in     } the   the     Overridefunc didreceivememorywarning () { About super.didreceivememorywarning () the     } the}

3. Use upload task to upload files

1 func sessionupload () {2     //Upload Address3var url = nsurl (string:"http://hangge.com/")4     //Request5var request:nsurlrequest = nsurlrequest (url:url!)6      7Let session =nsurlsession.sharedsession ()8      9     //Uploading data streamsTenLet documents = nshomedirectory () +"/documents/1.png" Onevar imgdata =NSData (contentsoffile:documents) A       -var uploadtask =session.uploadtaskwithrequest (Request, Fromdata:imgdata) { -(data:nsdata!, response:nsurlresponse!, error:nserror!) -Voidinch the         //Once the upload is complete -println"Upload Complete") -     } -       +     //To start a task by using the Resume method - Uploadtask.resume () +}

iOS development--Network Swift chapter &nsurlsession loading data, downloading, uploading files