1. Use jsapi to open the debugging of wx.config of the page, prompting that the signature is wrong;

2. Since the signature is wrong, print the intermediate data step by step on the step of obtaining this data to see which one is wrong;

3. The result is to simulate get/CGI-bin/ticket/getticketaccess _ token = access _ token &; Error 400, wrong request parameter, wrong request parameter when getting jsapi_ticket. . . Troubled for a long time. It used to work. Reason: The problem is ACCESS_TOKEN. Tencent didn't say whether there will be special characters in the format of this token. When "JSSDK Description Document" said that httpGET requested jsapi_ticket, it didn't say that there would be special characters in this token. . . The token in PHP has no urlencode, so when there are special characters in the token, 400 will appear. When the get and post API are opened, urlencode will be used for request parameters with unknown format.