iOS--判断字符串NSString中数字、中文、大小写英文

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

NSLog(@"字符串中含有大写英文字母");
}else if((commitChar>96)&&(commitChar<123)){

NSLog(@"字符串中含有小写英文字母");
}else if((commitChar>47)&&(commitChar<58)){

NSLog(@"字符串中含有数字");
}else{

NSLog(@"字符串中含有非法字符");
}
}

//判断是否为整形：

- (BOOL)isPureInt:(NSString*)string{
NSScanner* scan = [NSScanner scannerWithString:string];
int val;
return[scan scanInt:&val] && [scan isAtEnd];
}
//判断是否为浮点形：
- (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:含非法字符，请输入纯数字！";
return;
}else{
NSLog(@"整形或浮点型");
}