The problem of displaying user name after java web login

CSDN Q & A 2022-05-14 14:42:18 阅读数:712


Pictured :


It has been extracted here 123, Finally, why did the judgment become null? solve !

Take the answer :

It is said that to judge whether a string is empty is to use empty Of , You can change it for reference
<c:if test="${empty value}"> value It's empty
<c:if test="${not empty value}"> value Not empty

版权声明:本文为[CSDN Q & A]所创,转载请带上原文链接,感谢。