NSPredicate类，指定过滤器的条件－－－董鑫

/*
比较和逻辑运算符
就像前面的例子中使用了==操作符，NSPredicate还支持>, >=, <, <=, !=, <>,还支持AND, OR, NOT（或写成C语言样式&&, ||, ! ），其中AND，OR，NOT还是不区分大小写的
*/

NSArray *array = [NSArray array];

NSPredicate *predicate = [NSPredicate predicateWithFormat:@"age <= 28"];
for (Student *student in array) {
//标示指定的对象是否满足谓语条件
if ([predicate evaluateWithObject:student]) {
NSLog(@"person name : %@",student.name);
}
}

//返回一个符合谓语条件的数组
NSArray *newArray = [array filteredArrayUsingPredicate:predicate];
for (Student *student in newArray) {
NSLog(@"person name : %@",student.name);
}

/*
关键字 IN,BEGINSWITH,ENDSWITH,CONTAINS,LIKE,大小写都可以.添加的限制性字符串一定要添加''
*/
Student *student = [[Student alloc]init];

NSPredicate *preIN = [NSPredicate predicateWithFormat:@"student.name IN {'rose','bruse'}"];
NSArray *student1 = [array filteredArrayUsingPredicate:preIN];
//以**开始beginswith
NSPredicate *preBeginsWith = [NSPredicate predicateWithFormat:@"student.name beginswith '滚犊子'"];
NSArray *student2 = [array filteredArrayUsingPredicate:preBeginsWith];
//以＊＊结尾endswith
NSPredicate *preEndsWith = [NSPredicate predicateWithFormat:@"student.name endswith '滚犊子'"];
NSArray *student3 = [array filteredArrayUsingPredicate:preEndsWith];
//包含contains
NSPredicate *preContains = [NSPredicate predicateWithFormat:@"student.name contains '滚犊子'"];
NSArray *student4 = [array filteredArrayUsingPredicate:preContains];
//模糊查询like
NSPredicate *preLike = [NSPredicate predicateWithFormat:@"student.name like '*%@*'",@"滚犊子"];
NSArray *student5 = [array filteredArrayUsingPredicate:preLike];