获取链接中各个参数值

//获取链接中各个参数值
- (NSDictionary *)getParamsWithUrlString:(NSString *)urlString
{
    if (urlString.length == 0) {
        NSLog(@"链接为空！");
        return @{};
    }
    //先截取问号
    NSArray * allElements = [urlString componentsSeparatedByString:@"?"];
    NSMutableDictionary * params = [NSMutableDictionary dictionary];
    if (allElements.count == 2) {
        //有参数或者？后面为空
        NSString * paramString = allElements[1];
        //获取参数对
        NSArray * paramsArray = [paramString componentsSeparatedByString:@"&"];
        if (paramsArray.count >= 2) {
            for (NSInteger i = 0; i<paramsArray.count; i++) {
                NSString * singleParamString = paramsArray[i];
                NSArray * singleParamSet = [singleParamString componentsSeparatedByString:@"="];
                if (singleParamSet.count == 2) {
                    NSString * key = singleParamSet[0];
                    NSString * value = singleParamSet[1];
                    if (key.length > 0 || value.length > 0) {
                        [params setObject:value.length > 0 ? value:@"" forKey:key.length > 0 ? key:@""];
                    }
                }
            }
        }else if (paramsArray.count == 1){ //无& url只有？后一个参数
            NSString * singleParamString = paramsArray[0];
            NSArray * singleParamSet = [singleParamString componentsSeparatedByString:@"="];
            if (singleParamSet.count == 2) {
                NSString * key = singleParamSet[0];
                NSString * value = singleParamSet[1];
                if (key.length > 0 || value.length > 0) {
                    [params setObject:value.length > 0 ? value:@"" forKey:key.length > 0 ? key:@""];
                }
            }else{
                //问号后面什么都没有 xxxx？ 无需处理
            }
        }
        //整合url及参数
        return [params copy];
    }else if (allElements.count > 2){
        NSLog(@"链接不合法！链接包含多个？");
        return @{};
    }else{
        NSLog(@"链接不包含参数!");
        return @{};
    }
}

使用:

NSString * url = @"https://www.aaa.com/?key1=value1&key2=value2";
NSDictionary * dic = [self getParamsWithUrlString:url];