NSString *testString = @"中文123ljfLJF";
    NSInteger alength = [testString length];

    for (int i = 0; i<alength; i++) {
        char commitChar = [testString characterAtIndex:i];
        NSString *temp = [testString substringWithRange:NSMakeRange(i,1)];
        const char *u8Temp = [temp UTF8String];
        if
 
 (3==strlen(u8Temp)){

            NSLog(@"字串中含有中文");
        }else if((commitChar>64)&&(commitChar<91)){

            NSLog(@"字串中含有大寫英文字母");
        }else if((commitChar>96)&&(commitChar<123)){

            NSLog(@"字串中含有小寫英文字母");
        }else if((commitChar>47)&&(commitChar<58
 
)){

            NSLog(@"字串中含有數字");
        }else{

            NSLog(@"字串中含有非法字元");
        }
    }

//判斷是否為整形：

- (BOOL)isPureInt:(NSString*)string{
    NSScanner* scan = [NSScanner scannerWithString:string];
    int val;
    return[scan scanInt:&val] && [scan isAtEnd];
}
//判斷是否為浮點形：
- (BOOL
 
)isPureFloat:(NSString*)string{
    NSScanner* scan = [NSScanner scannerWithString:string];
    float val;
    return[scan scanFloat:&val] && [scan isAtEnd];
}
if( ![self isPureInt:textField.text] || ![self isPureFloat:textField.text]){
                textField.textColor = [UIColor redColor];
                textField.text = @"警告:含非法字元，請輸入純數字！";
                return;
            }else{
                NSLog(@"整形或浮點型");
            }