小编Amn*_*sia的帖子

因为这么多个小时,我被困在一个愚蠢的坏访问.我完全找不到它.我希望你们中的一些人能够向我展示答案.在下面的代码中它出现在行上:NSString * stringCallVisit = [[NSString alloc]initWithFormat:..... 我无法理解,除参数theIntervention外,所有对象都是方法的本地对象.

如果我评论该方法NSString * stringCallVisit = [[NSString alloc]initWithFormat:...,即使我这样做id obj = callVisit.injectionby;,也不会出现不良访问; 所以我认为不良访问不是来自callVisit对象,而是来自stringCallVisit对象.但是为什么我只是在出现坏访问的时候实例化它.

谢谢你的帮助,

-(NSString*)getCallVisitForIntervention:(Intervention*)theIntervention
{

NSManagedObjectContext *context = [iPad_TestAppDelegate mainContext];
NSError *error;

NSFetchRequest *requestCallVisit = [[NSFetchRequest alloc]init];
[requestCallVisit setEntity:[NSEntityDescription entityForName:@"CallVisit" inManagedObjectContext:context]];

NSPredicate *predicateInterventionID = [NSPredicate predicateWithFormat:@"intervention_id = %@",theIntervention.id];
[requestCallVisit setPredicate:predicateInterventionID];        

NSMutableArray *callVisits = [[context executeFetchRequest:requestCallVisit error:&error]mutableCopy];



NSString *xml  = @"<CallVisits>";

for(CallVisit *callVisit in callVisits) 
{

    NSString * stringCallVisit = [[NSString alloc]initWithFormat:
                                  @"<CallVisit>"
                                  "<id>%@</id>"
                                  "<injectionby>%@</injectionby>"
                                  "<injectionspot>%@</injectionspot>"
                                  "<intervention_id>%@</intervention_id>"
                                  "<fls>%d</fls>"
                                  "<weight>%d</weight>"
                                  "<height>%d</height>"
                                  "<painAtInjection>%d</painAtInjection>" …