UWP 在 System.Nullable 上编译互操作代码错误<string></string>

Question

我有一个 UWP 项目

当我想在发布配置中构建此解决方案时，出现以下错误

  obj\x64\Release\ilc\intermediate\BelledonneCommunications.Linphone.App.McgInterop\Data.g.cs(110561,148): error CS0453
  : The type 'string' must be a non-nullable value type in order to use it as parameter 'T' in the generic type or meth
  od 'Nullable<T>'
  obj\x64\Release\ilc\intermediate\BelledonneCommunications.Linphone.App.McgInterop\Data.g.cs(110562,148): error CS0453
  : The type 'string' must be a non-nullable value type in order to use it as parameter 'T' in the generic type or meth
  od 'Nullable<T>'
  obj\x64\Release\ilc\intermediate\BelledonneCommunications.Linphone.App.McgInterop\ImplTypes.g.cs(235776,50): error CS
  0453: The type 'string' must be a non-nullable value type in order to use it as parameter 'T' in the generic type or
  method 'Nullable<T>'
  obj\x64\Release\ilc\intermediate\BelledonneCommunications.Linphone.App.McgInterop\ImplTypes.g.cs(235837,41): error CS
  0453: The type 'string' must be a non-nullable value type in order to use it as parameter 'T' in the generic type or
  method 'Nullable<T>'

我的问题是为什么 UWP 在 ImplTypes.g.cs 中生成System.Nullable<string> ？

Answer 1

类型“string”必须是不可为空的值类型，才能在泛型类型或方法“Nullable”中用作参数“T”

尝试将传入的字符串定义更改为可为空的字段，例如string? .