字符串使用
//字符串和某个字符串相等
NSPredicate *predicate = [NSPredicatepredicateWithFormat:@"SELF
== %@",@"predicate"];
//字符串包含某个字符串
predicate1 = [NSPredicatepredicateWithFormat:@"SELF
Contains %@",@"ing"];
//从数组中查找某个字符串或包含某种特征的字符串
NSArray *array = [NSArrayarrayWithObjects:@"shanghai",@"beijing",@"tianjing",nil];
NSPredicate *predicate1 = [NSPredicate
predicateWithFormat:@"SELF == 'shanghai'"];
NSMutableArray *resultArray =
nil;
resultArray = [[arrayfilteredArrayUsingPredicate:predicate1]mutableCopy];
if (resultArray.count ==
0)
{
NSLog(@"没有上海");
}
else
{
NSLog(@"%@",[resultArray
objectAtIndex:0]);
}
[resultArray
removeAllObjects];
predicate1 = [NSPredicatepredicateWithFormat:@"SELF
Contains %@",@"ing"];
resultArray = [[arrayfilteredArrayUsingPredicate:predicate1]mutableCopy];
for (int i =
0; i < resultArray.count; i++)
{
NSLog(@"%@",[resultArray
objectAtIndex:i]);
}
//字符串的模糊匹配
predicate = [NSPredicatepredicateWithFormat:@"SELF LIKE［cd]
'*hh*'"];
predicate = [NSPredicatepredicateWithFormat:@"SELF
BEGINSWITH 'A'"];
predicate1 = [NSPredicatepredicateWithFormat:@"SELF ENDSWITH 't'"];
if ([predicate evaluateWithObject:@"Art"] && [predicate1evaluateWithObject:@"Art"])
{
NSLog(@"以A开头,以t结尾");
}
注:[c]不区分大小写[d]不区分发音符号即没有重音符号[cd]既不区分大小写，也不区分发音符号。
正则表达式的使用
1.邮箱地址校验
-(BOOL) isValidEmail:(NSString *)str
{
NSString *strRegex =@"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{1,3}";
NSPredicate *predicate = [NSPredicate
predicateWithFormat:@"SELF MATCHES %@",strRegex];
return [predicate
evaluateWithObject:str];
}
2.IP地址校验
-(BOOL) isIPAddress:(NSString *) str
{
NSString *strRegex =@"[0-9]{1,3}+\\.[0-9]{1,3}+\\.[0-9]{1,3}+\\.[0-9]{1,3}";
NSPredicate *predicate = [NSPredicate
predicateWithFormat:@"SELF MATCHES %@",strRegex];
return [predicate
evaluateWithObject:str];
}