Ios 在coredata中获取数据 -(void)getRecords { NSFetchRequest*fetchRequest=[[NSFetchRequest alloc]init]; NSEntityDescription*实体=[NSEntityDescription entityForName:@“CustomerOrder” inManagedObjectContext:self.managedObjectContext]; [FetchRequestSetEntity:entity]; n错误*错误; NSArray*fetchedRecords=[self.managedObjectContext executeFetchRequest:fetchRequest错误:&错误]; if(fetchedRecords) { if(fetchedRecords.count==0)//创建新实体 { NSLog(“Balaiah babu”); } 其他的 { 整数计数=0; 对于.h文件中的(inti=0;i
Ios 在coredata中获取数据 -(void)getRecords { NSFetchRequest*fetchRequest=[[NSFetchRequest alloc]init]; NSEntityDescription*实体=[NSEntityDescription entityForName:@“CustomerOrder” inManagedObjectContext:self.managedObjectContext]; [FetchRequestSetEntity:entity]; n错误*错误; NSArray*fetchedRecords=[self.managedObjectContext executeFetchRequest:fetchRequest错误:&错误]; if(fetchedRecords) { if(fetchedRecords.count==0)//创建新实体 { NSLog(“Balaiah babu”); } 其他的 { 整数计数=0; 对于.h文件中的(inti=0;i,ios,iphone,core-data,ios7,Ios,Iphone,Core Data,Ios7,-(void)getRecords { NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"CustomerOrder" inManagedObjectContext:self.ma
-(void)getRecords
{
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"CustomerOrder"
inManagedObjectContext:self.managedObjectContext];
[fetchRequest setEntity:entity];
NSError* error;
NSArray *fetchedRecords = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error];
if (fetchedRecords)
{
if (fetchedRecords.count == 0) //create new Entity
{
NSLog(@"Balaiah babu");
}
else
{
int count =0;
for (int i=0; i<fetchedRecords.count; i++) {
CustomerOrder * record = [fetchedRecords objectAtIndex:i];
NSLog(@"%@,%@,%@,%@,%@,%@,%@,%@,%@,%@,%@",record.customer_id,record.order_id,record.outletLatitude,record.outletLongitude,record.trigger_days,record.trigger_end_date,record.trigger_from_time,record.trigger_no_days,record.trigger_radius,record.trigger_start_date,record.trigger_to_time);
NSLog(@"%d",count++);
}
}
}
}
在.m文件中
-(void)getRecords
{
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"CustomerOrder"
inManagedObjectContext:self.managedObjectContext];
[fetchRequest setEntity:entity];
NSError* error;
NSArray *fetchedRecords = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error];
if (fetchedRecords)
{
if (fetchedRecords.count == 0) //create new Entity
{
NSLog(@"Balaiah babu");
}
else
{
int count =0;
for (int i=0; i<fetchedRecords.count; i++) {
CustomerOrder * record = [fetchedRecords objectAtIndex:i];
NSLog(@"%@,%@,%@,%@,%@,%@,%@,%@,%@,%@,%@",record.customer_id,record.order_id,record.outletLatitude,record.outletLongitude,record.trigger_days,record.trigger_end_date,record.trigger_from_time,record.trigger_no_days,record.trigger_radius,record.trigger_start_date,record.trigger_to_time);
NSLog(@"%d",count++);
}
}
}
}
获取实体“信息”
获取实体请求
NSEntityDescription *entity =
[NSEntityDescription entityForName:@"Info"
inManagedObjectContext:managedObjectContext];
获取记录并处理错误
NSFetchRequest *request = [[NSFetchRequest alloc] init];
[request setEntity:entity];
将提取的数据保存到数组中
NSMutableArray *mutableFetchResults =
[[managedObjectContext executeFetchRequest:request
error:&error] mutableCopy];
if (!mutableFetchResults)
{
Nslog(@"nil");
}
它仍然将mutableFetchResults显示为nil,但如果(!mutableFetchResults){Nslog(@“nil”);}您如何验证
fetchedRecords
是否为nil,则会出现这种情况?
NSLog(@"get_Result==%@",[mutableFetchResults valueForKey:@"fname"]);