How to Retrive and Store NSArray from sqlite DB in iOS -


i have array itemqtyarray storing in sqlite table as:

    nsdata *todata = [nskeyedarchiver archiveddatawithrootobject:self.itemqtyarray];      nsstring *insertsql = [nsstring stringwithformat: @"insert ordertable(itemdesc,itemqty)values( \"%@\",\"%@\");",datastring2,todata];

and retrieving :

    const void *itemqty = sqlite3_column_text(statement, 2);     nsinteger qtybytes = sqlite3_column_bytes(statement, 2);     nsdata *data2 = [nsdata datawithbytes:itemqty length:qtybytes];     nsarray *myarrayfromdb = [[nsarray alloc]init];     myarrayfromdb = [nskeyedunarchiver unarchiveobjectwithdata:data2];     [self.itemqtyarray addobjectsfromarray:myarrayfromdb];

but getting exception @ line

    myarrayfromdb = [nskeyedunarchiver unarchiveobjectwithdata:data2];

terminating app due uncaught exception 'nsinvalidargumentexception', reason: 

    '-[__nscfdata objectforkey:]: unrecognized selector sent instance

please tell wrong

nsdata *todata = [nskeyedarchiver archiveddatawithrootobject:array];

instead of should pass nsdictionary

nsdata *todata = [nskeyedarchiver archiveddatawithrootobject:dictionary];

or

o convert generic array nsdata, need archiver! if know how feed nsdata, know how use nskeyedarchiver. so:

nsarray* array= ... ; nsdata* data=[nskeyedarchiver archiveddatawithrootobject:array];

of course elements in array needs implement nscoding protocol


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