Solve the problem of garbled background data of ajax request

// Convert encoding to prevent ajax garbled 
response.setHeader ( "content-type" , "text/html; charset=UTF-8") ; 
response.setCharacterEncoding ( "UTF-8") ; 
request.setCharacterEncoding ( "UTF-8" ) ; 

these three sentences must be added to the beginning of the method. 

For example:

Front page:

Pro test useful original --wangchunyang