title: How can change code in Model.tt in Entity Framework to put attribute of key over the first integer property of class of database in Entity Framework
body: <p>I am writing an OData project in Asp.Net and I have a database with too many tables (more than one thousand) and none of these tables have a primary key. I'm not allowed to change the database and I must call the tables of database with Entity Framework in Visual Studio. </p>
  
  <p>When I run the program then in browser I will encounter with error: </p>
  
  <blockquote>
    <p>The entity set 'Locations' is based on type 'SIDS_Odata.Models.Location' that has no keys defined</p>
  </blockquote>
  
  <p>This error is because of that this table has no primary key. And when I put the attribute of key over one of the fields of this class in Entity Framework, then the other error like this that is related to the other table will be appeared in the browser and the classes that need to have attribute of key are too many and imagine that when I update model from database then all these attributes will be removed and I must put this attribute again in every class. </p>
  
  <p>For solving this problem I know that I can make changed in text file in Entity Framework that its name in my project is "Model1.tt". This text file has text codes as below:</p>
  
  <pre><code>&lt;#@ template language="C#" debug="false" hostspecific="true"#&gt;
  &lt;#@ include file="EF6.Utility.CS.ttinclude"#&gt;&lt;#@ 
   output extension=".cs"#&gt;&lt;#
  
  const string inputFile = @"Model1.edmx";
  var textTransform = DynamicTextTransformation.Create(this);
  var code = new CodeGenerationTools(this);
  var ef = new MetadataTools(this);
  var typeMapper = new TypeMapper(code, ef, textTransform.Errors);
  var fileManager = EntityFrameworkTemplateFileManager.Create(this);
  var itemCollection = new EdmMetadataLoader(textTransform.Host, textTransform.Errors).CreateEdmItemCollection(inputFile);
  var codeStringGenerator = new CodeStringGenerator(code, typeMapper, ef);
  
  if (!typeMapper.VerifyCaseInsensitiveTypeUniqueness(typeMapper.GetAllGlobalItems(itemCollection), inputFile))
  {
      return string.Empty;
  }
  
  WriteHeader(codeStringGenerator, fileManager);
  
  foreach (var entity in typeMapper.GetItemsToGenerate&lt;EntityType&gt;(itemCollection))
  {
      fileManager.StartNewFile(entity.Name + ".cs");
      BeginNamespace(code);
  #&gt;
  &lt;#=codeStringGenerator.UsingDirectives(inHeader: false)#&gt;
  &lt;#=codeStringGenerator.EntityClassOpening(entity)#&gt;
  {
  &lt;#
      var propertiesWithDefaultValues = typeMapper.GetPropertiesWithDefaultValues(entity);
      var collectionNavigationProperties = typeMapper.GetCollectionNavigationProperties(entity);
      var complexProperties = typeMapper.GetComplexProperties(entity);
  
      if (propertiesWithDefaultValues.Any() || collectionNavigationProperties.Any() || complexProperties.Any())
      {
  #&gt;
      [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
      public &lt;#=code.Escape(entity)#&gt;()
      {
  &lt;#
          foreach (var edmProperty in propertiesWithDefaultValues)
          {
  #&gt;
          this.&lt;#=code.Escape(edmProperty)#&gt; = &lt;#=typeMapper.CreateLiteral(edmProperty.DefaultValue)#&gt;;
  &lt;#
          }
  
          foreach (var navigationProperty in collectionNavigationProperties)
          {
  #&gt;
          this.&lt;#=code.Escape(navigationProperty)#&gt; = new HashSet&lt;&lt;#=typeMapper.GetTypeName(navigationProperty.ToEndMember.GetEntityType())#&gt;&gt;();
  &lt;#
          }
  
          foreach (var complexProperty in complexProperties)
          {
  #&gt;
          this.&lt;#=code.Escape(complexProperty)#&gt; = new &lt;#=typeMapper.GetTypeName(complexProperty.TypeUsage)#&gt;();
  &lt;#
          }
  #&gt;
      }
  
  &lt;#
      }
  
      var simpleProperties = typeMapper.GetSimpleProperties(entity);
      if (simpleProperties.Any())
      {
          foreach (var edmProperty in simpleProperties)
          {
  #&gt;
      &lt;#=codeStringGenerator.Property(edmProperty)#&gt;
  &lt;#
          }
      }
  
      if (complexProperties.Any())
      {
  #&gt;
  
  &lt;#
          foreach(var complexProperty in complexProperties)
          {
  #&gt;
      &lt;#=codeStringGenerator.Property(complexProperty)#&gt;
  &lt;#
          }
      }
  
      var navigationProperties = typeMapper.GetNavigationProperties(entity);
      if (navigationProperties.Any())
      {
  #&gt;
  
  &lt;#
          foreach (var navigationProperty in navigationProperties)
          {
              if (navigationProperty.ToEndMember.RelationshipMultiplicity == RelationshipMultiplicity.Many)
              {
  #&gt;
      [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
  &lt;#
              }
  #&gt;
      &lt;#=codeStringGenerator.NavigationProperty(navigationProperty)#&gt;
  &lt;#
          }
      }
  #&gt;
  }
  &lt;#
      EndNamespace(code);
  }
  
  foreach (var complex in typeMapper.GetItemsToGenerate&lt;ComplexType&gt;(itemCollection))
  {
      fileManager.StartNewFile(complex.Name + ".cs");
      BeginNamespace(code);
  #&gt;
  &lt;#=codeStringGenerator.UsingDirectives(inHeader: false, includeCollections: false)#&gt;
  &lt;#=Accessibility.ForType(complex)#&gt; partial class &lt;#=code.Escape(complex)#&gt;
  {
  &lt;#
      var complexProperties = typeMapper.GetComplexProperties(complex);
      var propertiesWithDefaultValues = typeMapper.GetPropertiesWithDefaultValues(complex);
  
      if (propertiesWithDefaultValues.Any() || complexProperties.Any())
      {
  #&gt;
      public &lt;#=code.Escape(complex)#&gt;()
      {
  &lt;#
          foreach (var edmProperty in propertiesWithDefaultValues)
          {
  #&gt;
          this.&lt;#=code.Escape(edmProperty)#&gt; = &lt;#=typeMapper.CreateLiteral(edmProperty.DefaultValue)#&gt;;
  &lt;#
          }
  
          foreach (var complexProperty in complexProperties)
          {
  #&gt;
          this.&lt;#=code.Escape(complexProperty)#&gt; = new &lt;#=typeMapper.GetTypeName(complexProperty.TypeUsage)#&gt;();
  &lt;#
          }
  #&gt;
      }
  
  &lt;#
      }
  
      var simpleProperties = typeMapper.GetSimpleProperties(complex);
      if (simpleProperties.Any())
      {
          foreach(var edmProperty in simpleProperties)
          {
  #&gt;
      &lt;#=codeStringGenerator.Property(edmProperty)#&gt;
  &lt;#
          }
      }
  
      if (complexProperties.Any())
      {
  #&gt;
  
  &lt;#
          foreach(var edmProperty in complexProperties)
          {
  #&gt;
      &lt;#=codeStringGenerator.Property(edmProperty)#&gt;
  &lt;#
          }
      }
  #&gt;
  }
  &lt;#
      EndNamespace(code);
  }
  
  foreach (var enumType in typeMapper.GetEnumItemsToGenerate(itemCollection))
  {
      fileManager.StartNewFile(enumType.Name + ".cs");
      BeginNamespace(code);
  #&gt;
  &lt;#=codeStringGenerator.UsingDirectives(inHeader: false, includeCollections: false)#&gt;
  &lt;#
      if (typeMapper.EnumIsFlags(enumType))
      {
  #&gt;
  [Flags]
  &lt;#
      }
  #&gt;
  &lt;#=codeStringGenerator.EnumOpening(enumType)#&gt;
  {
  &lt;#
      var foundOne = false;
  
      foreach (MetadataItem member in typeMapper.GetEnumMembers(enumType))
      {
          foundOne = true;
  #&gt;
      &lt;#=code.Escape(typeMapper.GetEnumMemberName(member))#&gt; = &lt;#=typeMapper.GetEnumMemberValue(member)#&gt;,
  &lt;#
      }
  
      if (foundOne)
      {
          this.GenerationEnvironment.Remove(this.GenerationEnvironment.Length - 3, 1);
      }
  #&gt;
  }
  &lt;#
      EndNamespace(code);
  }
  
  fileManager.Process();
  
  #&gt;
  &lt;#+
  
  public void WriteHeader(CodeStringGenerator codeStringGenerator, EntityFrameworkTemplateFileManager fileManager)
  {
      fileManager.StartHeader();
  #&gt;
  //------------------------------------------------------------------------------
  // &lt;auto-generated&gt;
  // &lt;#=CodeGenerationTools.GetResourceString("Template_GeneratedCodeCommentLine1")#&gt;
  //
  // &lt;#=CodeGenerationTools.GetResourceString("Template_GeneratedCodeCommentLine2")#&gt;
  // &lt;#=CodeGenerationTools.GetResourceString("Template_GeneratedCodeCommentLine3")#&gt;
  // &lt;/auto-generated&gt;
  //------------------------------------------------------------------------------
  &lt;#=codeStringGenerator.UsingDirectives(inHeader: true)#&gt;
  &lt;#+
      fileManager.EndBlock();
  }
  
  public void BeginNamespace(CodeGenerationTools code)
  {
      var codeNamespace = code.VsNamespaceSuggestion();
      if (!String.IsNullOrEmpty(codeNamespace))
      {
  #&gt;
  namespace &lt;#=code.EscapeNamespace(codeNamespace)#&gt;
  {
  &lt;#+
          PushIndent("    ");
      }
  }
  
  public void EndNamespace(CodeGenerationTools code)
  {
      if (!String.IsNullOrEmpty(code.VsNamespaceSuggestion()))
      {
          PopIndent();
  #&gt;
  }
  &lt;#+
      }
  }
  
  public const string TemplateId = "CSharp_DbContext_Types_EF6";
  
  public class CodeStringGenerator
  {
      private readonly CodeGenerationTools _code;
      private readonly TypeMapper _typeMapper;
      private readonly MetadataTools _ef;
  
      public CodeStringGenerator(CodeGenerationTools code, TypeMapper typeMapper, MetadataTools ef)
      {
          ArgumentNotNull(code, "code");
          ArgumentNotNull(typeMapper, "typeMapper");
          ArgumentNotNull(ef, "ef");
  
          _code = code;
          _typeMapper = typeMapper;
          _ef = ef;
      }
  
      public string Property(EdmProperty edmProperty)
      {
          return string.Format(
              CultureInfo.InvariantCulture,
              "{0} {1} {2} {{ {3}get; {4}set; }}",
              Accessibility.ForProperty(edmProperty),
              _typeMapper.GetTypeName(edmProperty.TypeUsage),
              _code.Escape(edmProperty),
              _code.SpaceAfter(Accessibility.ForGetter(edmProperty)),
              _code.SpaceAfter(Accessibility.ForSetter(edmProperty)));
      }
  
      public string NavigationProperty(NavigationProperty navProp)
      {
          var endType = _typeMapper.GetTypeName(navProp.ToEndMember.GetEntityType());
          return string.Format(
              CultureInfo.InvariantCulture,
              "{0} {1} {2} {{ {3}get; {4}set; }}",
              AccessibilityAndVirtual(Accessibility.ForNavigationProperty(navProp)),
              navProp.ToEndMember.RelationshipMultiplicity == RelationshipMultiplicity.Many ? ("ICollection&lt;" + endType + "&gt;") : endType,
              _code.Escape(navProp),
              _code.SpaceAfter(Accessibility.ForGetter(navProp)),
              _code.SpaceAfter(Accessibility.ForSetter(navProp)));
      }
  
      public string AccessibilityAndVirtual(string accessibility)
      {
          return accessibility + (accessibility != "private" ? " virtual" : "");
      }
  
      public string EntityClassOpening(EntityType entity)
      {
          return string.Format(
              CultureInfo.InvariantCulture,
              "{0} {1}partial class {2}{3}",
              Accessibility.ForType(entity),
              _code.SpaceAfter(_code.AbstractOption(entity)),
              _code.Escape(entity),
              _code.StringBefore(" : ", _typeMapper.GetTypeName(entity.BaseType)));
      }
  
      public string EnumOpening(SimpleType enumType)
      {
          return string.Format(
              CultureInfo.InvariantCulture,
              "{0} enum {1} : {2}",
              Accessibility.ForType(enumType),
              _code.Escape(enumType),
              _code.Escape(_typeMapper.UnderlyingClrType(enumType)));
          }
  
      public void WriteFunctionParameters(EdmFunction edmFunction, Action&lt;string, string, string, string&gt; writeParameter)
      {
          var parameters = FunctionImportParameter.Create(edmFunction.Parameters, _code, _ef);
          foreach (var parameter in parameters.Where(p =&gt; p.NeedsLocalVariable))
          {
              var isNotNull = parameter.IsNullableOfT ? parameter.FunctionParameterName + ".HasValue" : parameter.FunctionParameterName + " != null";
              var notNullInit = "new ObjectParameter(\"" + parameter.EsqlParameterName + "\", " + parameter.FunctionParameterName + ")";
              var nullInit = "new ObjectParameter(\"" + parameter.EsqlParameterName + "\", typeof(" + TypeMapper.FixNamespaces(parameter.RawClrTypeName) + "))";
              writeParameter(parameter.LocalVariableName, isNotNull, notNullInit, nullInit);
          }
      }
  
      public string ComposableFunctionMethod(EdmFunction edmFunction, string modelNamespace)
      {
          var parameters = _typeMapper.GetParameters(edmFunction);
  
          return string.Format(
              CultureInfo.InvariantCulture,
              "{0} IQueryable&lt;{1}&gt; {2}({3})",
              AccessibilityAndVirtual(Accessibility.ForMethod(edmFunction)),
              _typeMapper.GetTypeName(_typeMapper.GetReturnType(edmFunction), modelNamespace),
              _code.Escape(edmFunction),
              string.Join(", ", parameters.Select(p =&gt; TypeMapper.FixNamespaces(p.FunctionParameterType) + " " + p.FunctionParameterName).ToArray()));
      }
  
      public string ComposableCreateQuery(EdmFunction edmFunction, string modelNamespace)
      {
          var parameters = _typeMapper.GetParameters(edmFunction);
  
          return string.Format(
              CultureInfo.InvariantCulture,
              "return ((IObjectContextAdapter)this).ObjectContext.CreateQuery&lt;{0}&gt;(\"[{1}].[{2}]({3})\"{4});",
              _typeMapper.GetTypeName(_typeMapper.GetReturnType(edmFunction), modelNamespace),
              edmFunction.NamespaceName,
              edmFunction.Name,
              string.Join(", ", parameters.Select(p =&gt; "@" + p.EsqlParameterName).ToArray()),
              _code.StringBefore(", ", string.Join(", ", parameters.Select(p =&gt; p.ExecuteParameterName).ToArray())));
      }
  
      public string FunctionMethod(EdmFunction edmFunction, string modelNamespace, bool includeMergeOption)
      {
          var parameters = _typeMapper.GetParameters(edmFunction);
          var returnType = _typeMapper.GetReturnType(edmFunction);
  
          var paramList = String.Join(", ", parameters.Select(p =&gt; TypeMapper.FixNamespaces(p.FunctionParameterType) + " " + p.FunctionParameterName).ToArray());
          if (includeMergeOption)
          {
              paramList = _code.StringAfter(paramList, ", ") + "MergeOption mergeOption";
          }
  
          return string.Format(
              CultureInfo.InvariantCulture,
              "{0} {1} {2}({3})",
              AccessibilityAndVirtual(Accessibility.ForMethod(edmFunction)),
              returnType == null ? "int" : "ObjectResult&lt;" + _typeMapper.GetTypeName(returnType, modelNamespace) + "&gt;",
              _code.Escape(edmFunction),
              paramList);
      }
  
      public string ExecuteFunction(EdmFunction edmFunction, string modelNamespace, bool includeMergeOption)
      {
          var parameters = _typeMapper.GetParameters(edmFunction);
          var returnType = _typeMapper.GetReturnType(edmFunction);
  
          var callParams = _code.StringBefore(", ", String.Join(", ", parameters.Select(p =&gt; p.ExecuteParameterName).ToArray()));
          if (includeMergeOption)
          {
              callParams = ", mergeOption" + callParams;
          }
  
          return string.Format(
              CultureInfo.InvariantCulture,
              "return ((IObjectContextAdapter)this).ObjectContext.ExecuteFunction{0}(\"{1}\"{2});",
              returnType == null ? "" : "&lt;" + _typeMapper.GetTypeName(returnType, modelNamespace) + "&gt;",
              edmFunction.Name,
              callParams);
      }
  
      public string DbSet(EntitySet entitySet)
      {
          return string.Format(
              CultureInfo.InvariantCulture,
              "{0} virtual DbSet&lt;{1}&gt; {2} {{ get; set; }}",
              Accessibility.ForReadOnlyProperty(entitySet),
              _typeMapper.GetTypeName(entitySet.ElementType),
              _code.Escape(entitySet));
      }
  
      public string UsingDirectives(bool inHeader, bool includeCollections = true)
      {
          return inHeader == string.IsNullOrEmpty(_code.VsNamespaceSuggestion())
              ? string.Format(
                  CultureInfo.InvariantCulture,
                  "using System.ComponentModel.DataAnnotations;"+Environment.NewLine+
                  "{0}using System;{1}" +
                  "{2}",
                  inHeader ? Environment.NewLine : "",
                  includeCollections ? (Environment.NewLine + "using System.Collections.Generic;") : "",
                  inHeader ? "" : Environment.NewLine)
              : "";
      }
  }
  
  public class TypeMapper
  {
      private const string ExternalTypeNameAttributeName = @"http://schemas.microsoft.com/ado/2006/04/codegeneration:ExternalTypeName";
      private readonly System.Collections.IList _errors;
      private readonly CodeGenerationTools _code;
      private readonly MetadataTools _ef;
  
      public TypeMapper(CodeGenerationTools code, MetadataTools ef, System.Collections.IList errors)
      {
          ArgumentNotNull(code, "code");
          ArgumentNotNull(ef, "ef");
          ArgumentNotNull(errors, "errors");
  
          _code = code;
          _ef = ef;
          _errors = errors;
      }
  
      public static string FixNamespaces(string typeName)
      {
          return typeName.Replace("System.Data.Spatial.", "System.Data.Entity.Spatial.");
      }
  
      public string GetTypeName(TypeUsage typeUsage)
      {
          return typeUsage == null ? null : GetTypeName(typeUsage.EdmType, _ef.IsNullable(typeUsage), modelNamespace: null);
      }
  
      public string GetTypeName(EdmType edmType)
      {
          return GetTypeName(edmType, isNullable: null, modelNamespace: null);
      }
  
      public string GetTypeName(TypeUsage typeUsage, string modelNamespace)
      {
          return typeUsage == null ? null : GetTypeName(typeUsage.EdmType, _ef.IsNullable(typeUsage), modelNamespace);
      }
  
      public string GetTypeName(EdmType edmType, string modelNamespace)
      {
          return GetTypeName(edmType, isNullable: null, modelNamespace: modelNamespace);
      }
  
      public string GetTypeName(EdmType edmType, bool? isNullable, string modelNamespace)
      {
          if (edmType == null)
          {
              return null;
          }
  
          var collectionType = edmType as CollectionType;
          if (collectionType != null)
          {
              return String.Format(CultureInfo.InvariantCulture, "ICollection&lt;{0}&gt;", GetTypeName(collectionType.TypeUsage, modelNamespace));
          }
  
          var typeName = _code.Escape(edmType.MetadataProperties
                                  .Where(p =&gt; p.Name == ExternalTypeNameAttributeName)
                                  .Select(p =&gt; (string)p.Value)
                                  .FirstOrDefault())
              ?? (modelNamespace != null &amp;&amp; edmType.NamespaceName != modelNamespace ?
                  _code.CreateFullName(_code.EscapeNamespace(edmType.NamespaceName), _code.Escape(edmType)) :
                  _code.Escape(edmType));
  
          if (edmType is StructuralType)
          {
              return typeName;
          }
  
          if (edmType is SimpleType)
          {
              var clrType = UnderlyingClrType(edmType);
              if (!IsEnumType(edmType))
              {
                  typeName = _code.Escape(clrType);
              }
  
              typeName = FixNamespaces(typeName);
  
              return clrType.IsValueType &amp;&amp; isNullable == true ?
                  String.Format(CultureInfo.InvariantCulture, "Nullable&lt;{0}&gt;", typeName) :
                  typeName;
          }
  
          throw new ArgumentException("edmType");
      }
  
      public Type UnderlyingClrType(EdmType edmType)
      {
          ArgumentNotNull(edmType, "edmType");
  
          var primitiveType = edmType as PrimitiveType;
          if (primitiveType != null)
          {
              return primitiveType.ClrEquivalentType;
          }
  
          if (IsEnumType(edmType))
          {
              return GetEnumUnderlyingType(edmType).ClrEquivalentType;
          }
  
          return typeof(object);
      }
  
      public object GetEnumMemberValue(MetadataItem enumMember)
      {
          ArgumentNotNull(enumMember, "enumMember");
  
          var valueProperty = enumMember.GetType().GetProperty("Value");
          return valueProperty == null ? null : valueProperty.GetValue(enumMember, null);
      }
  
      public string GetEnumMemberName(MetadataItem enumMember)
      {
          ArgumentNotNull(enumMember, "enumMember");
  
          var nameProperty = enumMember.GetType().GetProperty("Name");
          return nameProperty == null ? null : (string)nameProperty.GetValue(enumMember, null);
      }
  
      public System.Collections.IEnumerable GetEnumMembers(EdmType enumType)
      {
          ArgumentNotNull(enumType, "enumType");
  
          var membersProperty = enumType.GetType().GetProperty("Members");
          return membersProperty != null 
              ? (System.Collections.IEnumerable)membersProperty.GetValue(enumType, null)
              : Enumerable.Empty&lt;MetadataItem&gt;();
      }
  
      public bool EnumIsFlags(EdmType enumType)
      {
          ArgumentNotNull(enumType, "enumType");
  
          var isFlagsProperty = enumType.GetType().GetProperty("IsFlags");
          return isFlagsProperty != null &amp;&amp; (bool)isFlagsProperty.GetValue(enumType, null);
      }
  
      public bool IsEnumType(GlobalItem edmType)
      {
          ArgumentNotNull(edmType, "edmType");
  
          return edmType.GetType().Name == "EnumType";
      }
  
      public PrimitiveType GetEnumUnderlyingType(EdmType enumType)
      {
          ArgumentNotNull(enumType, "enumType");
  
          return (PrimitiveType)enumType.GetType().GetProperty("UnderlyingType").GetValue(enumType, null);
      }
  
      public string CreateLiteral(object value)
      {
          if (value == null || value.GetType() != typeof(TimeSpan))
          {
              return _code.CreateLiteral(value);
          }
  
          return string.Format(CultureInfo.InvariantCulture, "new TimeSpan({0})", ((TimeSpan)value).Ticks);
      }
  
      public bool VerifyCaseInsensitiveTypeUniqueness(IEnumerable&lt;string&gt; types, string sourceFile)
      {
          ArgumentNotNull(types, "types");
          ArgumentNotNull(sourceFile, "sourceFile");
  
          var hash = new HashSet&lt;string&gt;(StringComparer.InvariantCultureIgnoreCase);
          if (types.Any(item =&gt; !hash.Add(item)))
          {
              _errors.Add(
                  new CompilerError(sourceFile, -1, -1, "6023",
                      String.Format(CultureInfo.CurrentCulture, CodeGenerationTools.GetResourceString("Template_CaseInsensitiveTypeConflict"))));
              return false;
          }
          return true;
      }
  
      public IEnumerable&lt;SimpleType&gt; GetEnumItemsToGenerate(IEnumerable&lt;GlobalItem&gt; itemCollection)
      {
          return GetItemsToGenerate&lt;SimpleType&gt;(itemCollection)
              .Where(e =&gt; IsEnumType(e));
      }
  
      public IEnumerable&lt;T&gt; GetItemsToGenerate&lt;T&gt;(IEnumerable&lt;GlobalItem&gt; itemCollection) where T: EdmType
      {
          return itemCollection
              .OfType&lt;T&gt;()
              .Where(i =&gt; !i.MetadataProperties.Any(p =&gt; p.Name == ExternalTypeNameAttributeName))
              .OrderBy(i =&gt; i.Name);
      }
  
      public IEnumerable&lt;string&gt; GetAllGlobalItems(IEnumerable&lt;GlobalItem&gt; itemCollection)
      {
          return itemCollection
              .Where(i =&gt; i is EntityType || i is ComplexType || i is EntityContainer || IsEnumType(i))
              .Select(g =&gt; GetGlobalItemName(g));
      }
  
      public string GetGlobalItemName(GlobalItem item)
      {
          if (item is EdmType)
          {
              return ((EdmType)item).Name;
          }
          else
          {
              return ((EntityContainer)item).Name;
          }
      }
  
      public IEnumerable&lt;EdmProperty&gt; GetSimpleProperties(EntityType type)
      {
          return type.Properties.Where(p =&gt; p.TypeUsage.EdmType is SimpleType &amp;&amp; p.DeclaringType == type);
      }
  
      public IEnumerable&lt;EdmProperty&gt; GetSimpleProperties(ComplexType type)
      {
          return type.Properties.Where(p =&gt; p.TypeUsage.EdmType is SimpleType &amp;&amp; p.DeclaringType == type);
      }
  </code></pre>
  
  <p>I know that the key attribute needs the using System.ComponentModel.DataAnnotations. and for this I have written this using in below method(in Model1.tt) as below:</p>
  
  <pre><code> public string UsingDirectives(bool inHeader, bool includeCollections = true)
  {
      return inHeader == string.IsNullOrEmpty(_code.VsNamespaceSuggestion())
          ? string.Format(
              CultureInfo.InvariantCulture,
              "using System.ComponentModel.DataAnnotations;"+Environment.NewLine+
              "{0}using System;{1}" +
              "{2}",
              inHeader ? Environment.NewLine : "",
              includeCollections ? (Environment.NewLine + "using System.Collections.Generic;") : "",
              inHeader ? "" : Environment.NewLine)
          : "";
  }
  </code></pre>
  
  <p>Now I do not know where to put the attribute of [key] in this text file(Model1.tt) in Entity Framework?</p>