Afnetworking to implement a breakpoint when the program restarts

2. Get the downloaded file size
4. -(unsigned long long) Filesizeforpath: (NSString *) path {
6. signed long long fileSize = 0;
8. Nsfilemanager *filemanager = [Nsfilemanager new]; //default is not thread safe
10. if ([FileManager Fileexistsatpath:path]) {
12. nserror *error = nil;
14. nsdictionary *filedict = [FileManager attributesofitematpath:path error:&error];
16. if (!error && filedict) {
18. FileSize = [filedict fileSize];
20. }
22. }
24. return fileSize;
26. }
28. Start download
30. -(void) Startdownload {
32. nsstring *downloadurl = @ "Http://www.xxx.com/xxx.zip";
34. nsstring *cachedirectory = [Nssearchpathfordirectoriesindomains (nscachesdirectory, NSUserDomainMask, YES)  Objectatindex:0];
36. nsstring *downloadpath = [cachedirectory stringbyappendingpathcomponent:@ "Xxx.zip"];
38. nsurlrequest *request = [nsurlrequest requestwithurl:[nsurl Urlwithstring:downloadurl];
40. //Check whether the file has been downloaded partially
42. Unsigned long long downloadedbytes = 0;
44. if ([[[Nsfilemanager Defaultmanager] Fileexistsatpath:downloadpath]) {
46. //Get the downloaded file length
48. Downloadedbytes = [self filesizeforpath:downloadpath];
50. if (Downloadedbytes > 0) {
52. nsmutableurlrequest *mutableurlrequest = [request mutablecopy];
54. nsstring *requestrange = [NSString stringwithformat:@ "bytes=%llu-", downloadedbytes];
56. [Mutableurlrequest setvalue:requestrange Forhttpheaderfield:@ "Range"];
58. request = Mutableurlrequest;
60. }
62. }
64. //Do not use the cache, avoid the problem of the breakpoint continued to pass
66. [[Nsurlcache Sharedurlcache] removecachedresponseforrequest:request];
68. //Download Request
70. afhttprequestoperation *operation = [[afhttprequestoperation alloc] initwithrequest:request];
72. //download Path
74. Operation. outputstream = [Nsoutputstream outputstreamtofileatpath:downloadpath append:YES];
76. //Download Progress callback
78. [Operation setdownloadprogressblock:^ (Nsuinteger bytesread, long Long totalbytesread, long long Totalbytesexpectedtoread) {
80. //Download Progress
82. Float progress = ((float) Totalbytesread + downloadedbytes)/(Totalbytesexpectedtoread + downloadedbytes);
84. }];
86. //Success and failure callbacks
88. [Operation setcompletionblockwithsuccess:^ (afhttprequestoperation *operation, ID responseobject) {
92. } failure:^ (afhttprequestoperation *operation, nserror *error) {
96. }];
98. [Operation start];
100. }

It is important to note that this is only useful for downloading zip packages, because there may be too many data to download files in other formats. When the file has been downloaded, call the function again, unable to determine whether the file has been downloaded completely, so it will be downloaded again, the server will report 416 error, the return will also output to the file, so that the file size is abnormal. However, the ZIP format is not affected.

Afnetworking to implement a breakpoint when the program restarts