IOS determines if the app starts for the first time

2. #define Last_run_version_key @ "Last_run_version_of_application"   

4. -(BOOL) isfirstload{

6. nsstring  * Currentversion = [[[nsbundle  mainbundle Span class= "VARs" style= "Margin:0px;padding:0px;border:none;color:rgb (221,0,0); background-color:inherit;" > infodictionary ]     

8. Objectforkey:@ "cfbundleshortversionstring"];

12. Nsuserdefaults    *defaults = [nsuserdefaults standarduserdefaults];

16. NSString    *lastrunversion = [Defaults objectforkey: Last_run_version_key];

20. if   (!lastRunVersion)  {    

22. [defaults setobject : CurrentVersion  forkey :LAST_RUN_ version_key];    

24. return     YES;

26. }

28. else if   (![ Lastrunversion  isequaltostring : CurrentVersion])  {    

30. [defaults setobject : CurrentVersion  forkey :LAST_RUN_ version_key];    

32. return     YES;

34. }

36. return     NO;

38. }

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IOS determines if the app starts for the first time