问题：json_decode($str)的结果为null，错误结果为4，属于语法错误。但是我不知道语法错误在哪里。网上找了各种方法都没用。最后把字符串扔到一个在线的json分析网站分析一下就知道问题出在哪里了。因为字符串中有淘宝链接。语法错误，改一下链接即可字符串内容如下：[{"product_id":12534665,"tuan_price":120,"tuan_sku_cms_scale":8,"order_limit_num":0,"user_limit_num":0,"module":[{"type":"input","name":"producttitle","comments":"producttitle,5-15characters","min_length":"5","max_length":"15","label_1":"","label_2":"","input_key":"title","input_val":"余兆麟产后收腹紧身衣","re??quired":1,"template":"","module_name":"title","err_msg":""},{"type":"input","name":"卖点1","comments":"营销文案，5个字符以内","min_length":0,"max_length":5,"label_1":"","label_2":"","input_key":"sub_desc_1","input_val":"超值108元","re??quired":1,"template":"""module_name":"sub_desc_1","err_msg":""},{"type":"input","name":"卖点2","comments":"营销文案，5个字符以内","min_length":0,"max_length":5,"label_1":"","label_2":"","input_key":"sub_desc_2","input_val":"塑身燃脂","re??quired":0,"template":"","module_name":"sub_desc_2","err_msg":""},{"type":"input","name":"卖点3","comments":"营销文案，5个字符以内","min_length":0,"max_length":5,"label_1":"","label_2":"","input_key":"sub_desc_3","input_val":"腹部整形术","re??quired":0,"模板":"","module_name":"sub_desc_3","err_msg":""},{"type":"input","name":"商品外链","comments":"","min_length":"","max_length":"","label_1":"","label_2":"","input_key":"outer_link","input_val":"https://detail.tmall.com/item.htm?spm=a220o.1000855.1998025129.3.7fab49231rhk2Y&pvid=d6619c06-2bb8-4ea1-a512-858b8b27d239&pos=3&acm=03054.1003.1.2768562&id=596662639804&scm=1007.16862.95220.23864_0_0&utparam={"x_hestia_source":"23864","x_object_type":"item","x_mt":0,"x_src":"23864","x_pos":3,"x_pvid":"d6619c06-2bb8-4ea1-a512-858b8b27d239","x_object_id":596662639804}&skuId=4313871398448","要求uired":1,"模板":"","信息_bottom":"
