Objective c 使用NSPredicate筛选NSR字典的NSArray
我有这样一个数组:Objective c 使用NSPredicate筛选NSR字典的NSArray,objective-c,ios,nsarray,nsdictionary,nspredicate,Objective C,Ios,Nsarray,Nsdictionary,Nspredicate,我有这样一个数组: NSArray* myArray=[NSArray arrayWithObjects: [NSDictionary dictionaryWithObjectsAndKeys:@"123",@"imageid",@"Jeff",@"imagename", nil], [NSDictionary dictionaryWithObjectsAndKeys:@"234",@"imageid",@
NSArray* myArray=[NSArray arrayWithObjects:
[NSDictionary dictionaryWithObjectsAndKeys:@"123",@"imageid",@"Jeff",@"imagename", nil],
[NSDictionary dictionaryWithObjectsAndKeys:@"234",@"imageid",@"Sophie",@"imagename", nil],
[NSDictionary dictionaryWithObjectsAndKeys:@"456",@"imageid",@"David",@"imagename", nil]
, nil];
我想得到一个包含如下内容的目标数组:{ 123,234,456 }
如何使用
NSPredicate
?试试这个。为此,您可能不需要NSPredicate
NSArray *targetArray = [myArray valueForKey:@"imageid"];
更新:
要更好地了解valueForKey,请参阅