#pragma mark -- 判断字符串是否只存在只有空格
+ (BOOL)isBlankString:(NSString *)string{
if (string == nil) {
return YES;
}
if (string == NULL) {
return YES;
}
if ([string isKindOfClass:[NSNull class]]) {
return YES;
}
if ([[string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] length]==0) {
return YES;
}
return NO;
}