c# isdefined
Sean Corfield recently blogged about the choice to use IsDefined vs. structKeyExists when trying to determine if a scoped variable (session, application, request, form url etc), exists or not.
肖恩·科菲尔德(Sean Corfield)最近在博客中写道，在尝试确定范围变量(会话，应用程序，请求，表单url等)是否存在时，选择使用IsDefined还是structKeyExists。
Sean talks about how certain dot noted variables will or won’t be seen with IsDefined, BUT I found the fact that IsDefined looks for ANY possible definition even when the variable you’re searching for has been scoped.
肖恩(Sean)谈到IsDefined如何显示或不显示某些点注释变量，但是我发现，即使您要搜索的变量已经确定范围，IsDefined也会寻找任何可能的定义。
Read his blurb to get the full effect.
阅读他的简介以获得完整的效果。
翻译自: https://www.sitepoint.com/isdefined-vs-structkeyexists/
c# isdefined
相关资源：jdk-8u281-windows-x64.exe