iOS 图片链接带中文空格

1.utf8转译
[str stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]

2.手动转码

+ (void)load {
   // 获取URLWithString:方法的地址
   Method URLWithStringMethod = class_getClassMethod(self, @selector(URLWithString:));
   // 获取BMW_URLWithString:方法的地址
   Method BMW_URLWithStringMethod = class_getClassMethod(self, @selector(BMW_URLWithString:));
   // 交换方法地址
   method_exchangeImplementations(URLWithStringMethod, BMW_URLWithStringMethod);
   
}
+ (NSURL *)BMW_URLWithString:(NSString *)URLString {
   NSString *newURLString = [self isChinese:URLString];
   return [NSURL BMW_URLWithString:newURLString];
}
//处理特殊字符
+ (NSString *)isChinese:(NSString *)str {
   NSString *newString = str;
   //遍历字符串中的字符
   for(int i=0; i< [str length];i++){
       int a = [str characterAtIndex:i];
       //汉字的处理
       if( a > 0x4e00 && a < 0x9fff)
       {
           NSString *oldString = [str substringWithRange:NSMakeRange(i, 1)];
           NSString *string = [oldString stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];
           newString = [newString stringByReplacingOccurrencesOfString:oldString withString:string];
       }
       //空格处理
       if ([newString containsString:@" "]) {
           newString = [newString stringByReplacingOccurrencesOfString:@" " withString:@"%20"];

       }
     //如果需要处理其它特殊字符,在这里继续判断处理即可.
   }
   return newString;
}