iOS中有三種方式來實現正則表達式的匹配。現在將他們都記錄在這里：
1.利用NSPredicate（謂詞）匹配
例如匹配有效郵箱：
NSString ＊email ＝ @“nijino_saki@163.com”； NSString *regex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+//.[A-Za-z]{2,4}"; NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex]; BOOL isValid = [predicate evaluateWithObject:email]; 謂詞匹配比較靈活，但是需要有謂詞的相關知識。
2.利用rangeOfString：option：直接查找
NSString *searchText = @"// Do any additional setup after loading the view, typically from a nib."; NSRange range = [searchText rangeOfString:@"(?:[^,])*//." options:NSRegularExpressionSearch]; if (range.location != NSNotFound) { NSLog(@"%@", [searchText substringWithRange:range]); } options中設定NSRegularExpressionSearch就是表示利用正則表達式匹配，會返回第一個匹配結果的位置。
3.使用正則表達式類
NSString *searchText = @"// Do any additional setup after loading the view, typically from a nib."; NSError *error = NULL;NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(?:[^,])*//." options:NSRegularExpressionCaseInsensitive error:&error];NSTextCheckingResult *result = [regex firstMatchInString:searchText options:0 range:NSMakeRange(0, [searchText length])];if (result) { NSLog(@"%@/n", [searchText substringWithRange:result.range]);} 使用系統的正則表達式類（NSRegularExpression）會返回匹配的多個結果。
實例：
1.驗證郵箱
+ (BOOL)validateEmail:(NSString *)email{ NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+//.[A-Za-z]{2,4}"; NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex]; return [emailTest evaluateWithObject:email];} NSPredicate是一個Foundation類，是用來查詢的，原理和用法都類似于SQL中的where。
2.驗證手機號
簡單的判斷方法
+ (BOOL)validatePhone:(NSString *)phone{ NSString *phoneRegex = @"1[3|5|7|8|][0-9]{9}"; NSPredicate *phoneTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", phoneRegex]; return [phoneTest evaluateWithObject:phone];} 這只是簡單地判斷手機號格式。其實手機的格式還是有一點復雜的。
詳細的判斷方法
//正則判斷手機號碼格式+ (BOOL)validatePhone:(NSString *)phone{ /** * 手機號碼 * 移動：134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188 * 聯通：130,131,132,152,155,156,185,186 * 電信：133,1349,153,180,189 */ NSString * MOBILE = @"^1(3[0-9]|5[0-35-9]|8[025-9])//d{8}$"; /** * 中國移動：China Mobile * 134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188 */ NSString * CM = @"^1(34[0-8]|(3[5-9]|5[017-9]|8[278])//d)//d{7}$"; /** * 中國聯通：China Unicom * 130,131,132,152,155,156,185,186 */ NSString * CU = @"^1(3[0-2]|5[256]|8[56])//d{8}$"; /** * 中國電信：China Telecom * 133,1349,153,180,189 */ NSString * CT = @"^1((33|53|8[09])[0-9]|349)//d{7}$"; /** * 大陸地區固話及小靈通 * 區號：010,020,021,022,023,024,025,027,028,029 * 號碼：七位或八位 */ // NSString * PHS = @"^0(10|2[0-5789]|//d{3})//d{7,8}$"; NSPredicate *regextestmobile = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", MOBILE]; NSPredicate *regextestcm = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CM]; NSPredicate *regextestcu = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CU]; NSPredicate *regextestct = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CT]; if (([regextestmobile evaluateWithObject:phone] == YES) || ([regextestcm evaluateWithObject:phone] == YES) || ([regextestct evaluateWithObject:phone] == YES) || ([regextestcu evaluateWithObject:phone] == YES)) { if([regextestcm evaluateWithObject:phone] == YES) { NSLog(@"China Mobile"); } else if([regextestct evaluateWithObject:phone] == YES) { NSLog(@"China Telecom"); } else if ([regextestcu evaluateWithObject:phone] == YES) { NSLog(@"China Unicom"); } else { NSLog(@"Unknow"); } return YES; } else { return NO; }} 
