"Code note" Saves the log log to a file

Code:

#import "AppDelegate.h" #import "RootViewController.h" @implementation appdelegate-(BOOL) application: (uiapplication *) Application Didfinishlaunchingwithoptions: (nsdictionary *) launchoptions{Self.window = [[UIWindow alloc]    Initwithframe:[[uiscreen Mainscreen] bounds];        Override point for customization after application launch.    Rootviewcontroller *rootvc=[[rootviewcontroller Alloc]init];    Uinavigationcontroller *nav=[[uinavigationcontroller ALLOC]INITWITHROOTVIEWCONTROLLER:ROOTVC];            Self.window.rootviewcontroller=nav;    Save log log to file #ifdef Bh_debug [self redirectnslogtodocumentfolder];    #else #endif self.window.backgroundColor = [Uicolor Whitecolor];    [Self.window makekeyandvisible]; return YES;}    -(void) redirectnslogtodocumentfolder{//If the Xcode is already connected, do not output to file if (Isatty (Stdout_fileno)) {return;    } uidevice *device = [Uidevice currentdevice]; If the emulator is not saved to the file if ([[Device model] hassuffix:@ "Simulator"]) {return; }//Save the NSLog print information to the log folder under the document directory Nsarray *paths = Nssearchpathfordirectoriesindomains (NSDocumentDirectory, N    Suserdomainmask, YES);        NSString *logdirectory = [[Paths objectatindex:0] stringbyappendingpathcomponent:@ "Log"];    Nsfilemanager *filemanager = [Nsfilemanager Defaultmanager];    BOOL fileexists = [FileManager fileexistsatpath:logdirectory]; if (!fileexists) {[FileManager createdirectoryatpath:logdirectory withintermediatedirectories:yes Attributes:nil    Error:nil];    } nsdateformatter *formatter = [[NSDateFormatter alloc] init];    [Formatter Setlocale:[[nslocale alloc] initwithlocaleidentifier:@ "ZH_CN"];    [Formatter setdateformat:@ "Yyyy-mm-dd HH:mm:ss"];    Save a new log file after each startup nsstring *datestr = [formatter stringfromdate:[nsdate date]];        NSString *logfilepath = [logdirectory stringbyappendingformat:@ "/%@.log", datestr]; Enter log into file Freopen ([LogFilePath cstringusingencoding:nsasciistringencoding], "A +", stdout);        Freopen ([LogFilePath cstringusingencoding:nsasciistringencoding], "A +", stderr); Uncaught objective-c Exception Log nssetuncaughtexceptionhandler (&uncaughtexceptionhandler);}    void Uncaughtexceptionhandler (nsexception* exception) {nsstring* name = [exception name];    nsstring* reason = [exception reason];    nsarray* symbols = [exception callstacksymbols];    When an exception occurs, the call stack nsmutablestring* strsymbols = [[Nsmutablestring alloc] init];        The string for which the call stack is spelled as an output log for (nsstring* item in symbols) {[Strsymbols appendstring:item];    [Strsymbols appendString: @ "\ r \ n"]; }//Save the crash log to the log folder under the document directory Nsarray *paths = Nssearchpathfordirectoriesindomains (NSDocumentDirectory, NSU    Serdomainmask, YES);        NSString *logdirectory = [[Paths objectatindex:0] stringbyappendingpathcomponent:@ "Log"];    Nsfilemanager *filemanager = [Nsfilemanager Defaultmanager]; if (![ FileManager Fileexistsatpath:logdirectory]) {[FileManager CREAtedirectoryatpath:logdirectory withintermediatedirectories:yes Attributes:nil Error:nil];    } nsstring *logfilepath = [logdirectory stringbyappendingpathcomponent:@ "UncaughtException.log"];    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];    [Formatter Setlocale:[[nslocale alloc] initwithlocaleidentifier:@ "ZH_CN"];    [Formatter setdateformat:@ "Yyyy-mm-dd HH:mm:ss"];        NSString *datestr = [formatter stringfromdate:[nsdate date]]; NSString *crashstring = [NSString stringwithformat:@ "<-%@->[uncaught Exception]\r\nname:%@, Reason:%@\r\n[Fe        Symbols Start]\r\n%@[Fe Symbols End]\r\n\r\n ", datestr, name, Reason, Strsymbols]; Write the error log to the file if (![ FileManager Fileexistsatpath:logfilepath]) {[Crashstring writetofile:logfilepath atomically:yes encoding:NSUTF8Str    Ingencoding Error:nil];        }else{nsfilehandle *outfile = [Nsfilehandle Filehandleforwritingatpath:logfilepath];        [OutFile Seektoendoffile]; [OutFile WRITedata:[crashstring Datausingencoding:nsutf8stringencoding]];    [OutFile CloseFile]; }//Send error log to mailbox//NSString *URLSTR = [NSString stringwithformat:@ "mailto://[email protected]?subject=    Bug report &body= Thank you for your cooperation!<br><br><br> error details: <br>%@ ", crashstring];    Nsurl *url = [Nsurl urlwithstring:[urlstr stringbyaddingpercentescapesusingencoding:nsutf8stringencoding]; [[UIApplication sharedapplication] openurl:url];}

"Code note" Saves the log log to a file