[EF] edmx 無法產生 Model class

在 VS V17.6.2 上開啟 WinForm 搭配 .NET Framework4.8.1 並使用 EF 6.4.4 時，發現不論是專案內原有 edmx 還是新建立 edmx，竟然都無法產生 Model class

以下圖來說，正常情況下 edmx 內有 Address 存在，AdventureWorks2019.tt 檔案下應該要產生 Address class 才對

AdventureWorks2019.Context.cs 檔案內有建立出 DbSet<Address>，但因為 Address class 沒有產生，會有紅色蚯蚓符號

相關錯誤訊息

錯誤		正在執行轉換: System.NullReferenceException: 並未將物件參考設定為物件的執行個體。
   於 Microsoft.VisualStudio.TextTemplating548217BD8377E326AEE514EAE722C9BA6586C4151F980CA7BACC70A5732FC55F588FBC8794326CD64388F9B4C50AD7729497DE610EBC8D6F64F48BB130F68063.GeneratedTextTransformation.DynamicTextTransformation.get_GenerationEnvironment()
   於 Microsoft.VisualStudio.TextTemplating548217BD8377E326AEE514EAE722C9BA6586C4151F980CA7BACC70A5732FC55F588FBC8794326CD64388F9B4C50AD7729497DE610EBC8D6F64F48BB130F68063.GeneratedTextTransformation.EntityFrameworkTemplateFileManager..ctor(Object textTransformation)
   於 Microsoft.VisualStudio.TextTemplating548217BD8377E326AEE514EAE722C9BA6586C4151F980CA7BACC70A5732FC55F588FBC8794326CD64388F9B4C50AD7729497DE610EBC8D6F64F48BB130F68063.GeneratedTextTransformation.EntityFrameworkTemplateFileManager.VsEntityFrameworkTemplateFileManager..ctor(Object textTemplating)
   於 Microsoft.VisualStudio.TextTemplating548217BD8377E326AEE514EAE722C9BA6586C4151F980CA7BACC70A5732FC55F588FBC8794326CD64388F9B4C50AD7729497DE610EBC8D6F64F48BB130F68063.GeneratedTextTransformation.EntityFrameworkTemplateFileManager.Create(Object textTransformation)
   於 Microsoft.VisualStudio.TextTemplating548217BD8377E326AEE514EAE722C9BA6586C4151F980CA7BACC70A5732FC55F588FBC8794326CD64388F9B4C50AD7729497DE610EBC8D6F64F48BB130F68063.GeneratedTextTransformation.TransformText()

在網路上找到該篇討論 - Create or recreate a Model does not works any more for winform .net framework solutions 確定問題點在哪，雖然有人提出該問題已經修正，詳見該 commit，但在我的VS IDE 環境內還是出現該問題

根據討論內容，直接修正 EF6.Utility.CS (C:\Program Files\Microsoft Visual Studio\2022\Community\Common7\IDE\Extensions\Microsoft\Entity Framework Tools\Templates\Includes\EF6.Utility.CS)

修正後內容

private DynamicTextTransformation(object instance)
{
    _instance = instance;
    Type type = _instance.GetType();
    _write = type.GetMethod("Write", new Type[] { typeof(string) });
    _writeLine = type.GetMethod("WriteLine", new Type[] { typeof(string) });
    _generationEnvironment = type.GetProperty("GenerationEnvironment"); // 修正該行
    _host = type.GetProperty("Host");
    _errors = type.GetProperty("Errors");
}

修正內容為

// 把
_generationEnvironment = type.GetProperty("GenerationEnvironment", BindingFlags.Instance | BindingFlags.NonPublic);
// 修正為
_generationEnvironment = type.GetProperty("GenerationEnvironment");

重開 VS 後，edmx 就恢復正常啦

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