.net Core 2.0 Assembly，带T4：无法加载文件或程序集'System.Runtime，Version = 4.2.0.0

Question

我有一个T4模板，我引用了一个不同的程序集：

var code = new CodeGenHelper();

然后我尝试在该dll中创建唯一类的实例：

Severity    Code    Description Project File    Line    Suppression State
Error       Running transformation: System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=4.2.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'System.Runtime, Version=4.2.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at Microsoft.VisualStudio.TextTemplatingCFC642B0A338D346F5BAF55401746E231DEE772554EE3570FFA3AA2898966BCA1378D2C2DC8325581610CA4D66B8A56C97E5C4A6AD35B2C18FAAAF37E1A6B7C9.GeneratedTextTransformation.TransformText()
   at System.Dynamic.UpdateDelegates.UpdateAndExecute1[T0,TRet](CallSite site, T0 arg0)
   at Microsoft.VisualStudio.TextTemplating.TransformationRunner.PerformTransformation()

当我运行T4模板（又名，保存）时，我收到以下错误：

using System;
using System.Linq;
using System.Collections.Generic;
using System.Reflection;
using Microsoft.CodeAnalysis.CSharp;

namespace Project.CodeGen
{
    public class CodeGenHelper
    {
        public CodeGenHelper()
        {

        }

        public string Derp(string herp)
        {
            ... do stuff
        }
    }
}

然后我添加了对

的引用

  

System.Runtime

（完全合格而不是），似乎都没有效果。

这就是Project.CodeGen源的样子（缩减）：

<p-table #dt  [value]="iToDoList" dataKey="ID"  [paginator]="true" [rowsPerPageOptions]="[10,50,100]" [rows]="10">
     <ng-template pTemplate="header">
         <tr>
            <th>ID</th>
            <th>Comment</th>
            <th>Action</th>
         </tr>
     </ng-template>
     <ng-template pTemplate="body" let-row>  
         <tr>
            <td>{{row.ID}}</td>
            <td>
                <div  *ngIf="!row.isEditable">{{row.Comment}}</div>
                <div *ngIf="row.isEditable">
                     <input type="text" [(ngModel)]="row.comment">
                </div>
            </td>
            <td><button (click)="editRow(row)">Edit</button></td>
            <td>                                
               <button (click)="save(row)">Save</button>
            </td>
          </tr>
     </ng-template>
</p-table>

我是否需要以某种方式引用System.Runtime，我认为核心无法进行？我需要引用像netstandard这样的东西吗？我很困惑，至少可以说。