字符串非空判断

#import "NSString+Addons.h"

@implementation NSString (Addons)

- (BOOL)isNotBlankString {
    if (!self) {
        return NO;
    }
    if ([self isKindOfClass:[NSNull class]]) {
        return NO;
    }
    if (!self.length) {
        return NO;
    }
    NSCharacterSet *set = [NSCharacterSet whitespaceAndNewlineCharacterSet];
    NSString *trimmedStr = [self stringByTrimmingCharactersInSet:set];
    if (!trimmedStr.length) {
        return NO;
    }
    return YES;
}

@end