所以我一直在研究Unity项目一段时间以来，几周前我每次尝试将visual studio连接到Unity时都会遇到多个错误。我得到的所有错误都与'UnityEngine.UI'有关。
CS0234 The type or namespace name 'UI' does not exist in the namespace 'UnityEngine' (are you missing an assembly reference?)
我根本没有编辑过解决方案文件，我也没有更改任何引用。
现在奇怪的是，当我构建获取错误列表时，但是如果我双击一个它将我带到错误位置然后所有错误消失，就像解决方案没问题。但是，如果我构建项目，我会收到所有错误......
我认为你可以重现这个错误的唯一方法是制作一个新的Unity项目（我正在使用5.3.3f1），创建一个脚本并包含这个命名空间
using UnityEngine.UI;
然后看看你是否可以构建项目。如果有人知道这个项目的解决方案会很棒：）
同样在我的“警告”窗口中，我有这3个
The primary reference "UnityEditor" could not be resolved because it has an indirect dependency on the framework assembly "System.Xml.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" which could not be resolved in the currently targeted framework. ".NETFramework,Version=v3.5,Profile=Unity Web v3.5".
The primary reference "UnityEngine.Networking" could not be resolved because it has an indirect dependency on the framework assembly "System.Xml.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" which could not be resolved in the currently targeted framework. ".NETFramework,Version=v3.5,Profile=Unity Web v3.5".
The primary reference "UnityEngine.UI" could not be resolved because it has an indirect dependency on the framework assembly "System.Xml.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" which could not be resolved in the currently targeted framework. ".NETFramework,Version=v3.5,Profile=Unity Web v3.5".
答案 0 :(得分：1)
当您的上一个构建目标是＆＃34; Web Player＆＃34;。
时，会发生这种情况