小编Lin*_*ung的帖子

我不知道为什么对我不起作用。我以管理员身份打开 powershell 并运行npm install -g @vue/cli. 我已经卸载了 vue-cli 并且再次重新安装不起作用。这是我的错误

PS C:\WINDOWS\system32> npm install -g @vue/cli
npm WARN deprecated cross-spawn-async@2.2.5: cross-spawn no longer requires a build toolchain, use it instead
C:\Users\Lin Aung\AppData\Roaming\npm\vue -> C:\Users\Lin Aung\AppData\Roaming\npm\node_modules\@vue\cli\bin\vue.js

> protobufjs@6.8.8 postinstall C:\Users\Lin Aung\AppData\Roaming\npm\node_modules\@vue\cli\node_modules\protobufjs
> node scripts/postinstall


> nodemon@1.18.10 postinstall C:\Users\Lin Aung\AppData\Roaming\npm\node_modules\@vue\cli\node_modules\nodemon
> node bin/postinstall || exit 0

npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.7 (node_modules\@vue\cli\node_modules\fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.7: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})

+ @vue/cli@3.5.0
added …

我有以下代码

int[] array = new int[10] { 4, 50 , 60 , 80 , 120 , 46 , 52 , 60 , 18 , 221};


var sum = (from num in array
           where ((num % 4) != 0 && (num % 6 ) != 0) && ((num % 2) != 0)
           select array);

Console.Write(sum.Sum());

问题是我无法使用Sum().它说

'System.Collections.Generic.IEnumerable'不包含'Sum'的定义和最佳扩展方法重载'System.Linq.Queryable.Sum(System.Linq.IQueryable)'

我怎么能这样做？