.net T4 模板 从模型获取表名 代码模板写法

背景：vs2017 、mysql数据库、T4模板、   安装了Devart T4 。

Devart T4  对T4模板进行高亮显示的编译器，支持T4调试。但是支持并不是特别好。创建ado数据模型后，自动生成的T4模板也会报错。。。不过聊胜于无。。。还是可以一用的

因为对T4模板的用法还是不是很了解，本着够用就好的原则，暂时不对这块深入学习。记录两种写法，备用

写法一：

1.来自创智博客黑马教程

2.使用<#@ include file="EF.Utility.CS.ttinclude"#>

3.写法比较简单

4.自行删除//后的内容

<#@ template language="C#" debug="false" hostspecific="true"#>
<#@ include file="EF.Utility.CS.ttinclude"#><#@ 
 output extension=".cs"#><#

string inputFile = @"..\\LingFeng.OA.Model\\DataModel.edmx"; //模型所在路径
CodeGenerationTools code = new CodeGenerationTools(this);
MetadataLoader loader= new MetadataLoader(this);
CodeRegion region = new CodeRegion(this);
MetadataTools ef = new MetadataTools(this);

EdmItemCollection ItemCollection =loader.CreateEdmItemCollection(inputFile);
string namespaceName=code.VsNamespaceSuggestion();
EntityFrameworkTemplateFileManager    fileManager = EntityFrameworkTemplateFileManager.Create(this);

#>
using LingFeng.OA.Model;//需修改

namespace LingFeng.OA.IDal//需修改
{
<#
foreach(EntityType entity in ItemCollection.GetItems<EntityType>().OrderBy(e=>e.Name))
{
#>
    public partial interface I<#=string.Concat(entity.Name.First<char>().ToString().ToUpper(),entity.Name.Substring(1))#>Dal: IBaseDal<<#=entity.Name#>>//此处应为mysql读到的模型都是小写,所以做了一个首字母转大写
    {

    }
<#}#>
}

写法二:

1.参考 DataModel.edmx 下 自动生成的的DataModel.tt的代码(谁让我完全不懂T4里的代码呢)

2.使用<#@ include file="EF6.Utility.CS.ttinclude"#>

3.保留  DataModel.tt  中定义的  public class TypeMapper  

(在读取模型的时候用了这类的方法,因为看的不是很懂所以就全部保留这个类了,觉得代码多的,可以把类中的没用的方法删除)

4.保留  DataModel.tt  中定义的  public static void ArgumentNotNull<T>(T arg, string name) where T : class  

(原因是EF6.Utility.CS.ttinclude  文件中调用了这个方法 ,但是没有定义?)

5.其他就容易了,代码比较长

6.自行删除//后的内容

ps:  EF6.Utility.CS.ttinclude  和  EF.Utility.CS.ttinclude  的比较实用32位版本的  notepad++  (缩写npp)   +  compare  插件    (插件比较早,64位不能装这个插件)

上代码~

<#@ template language="C#" debug="false" hostspecific="true"#>
<#@ include file="EF6.Utility.CS.ttinclude"#><#@ 
 output extension=".cs"#><#

const string inputFile = @"..\\LingFeng.OA.Model\\DataModel.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);


if (!typeMapper.VerifyCaseInsensitiveTypeUniqueness(typeMapper.GetAllGlobalItems(itemCollection), inputFile))
{
    return string.Empty;
}

#>
using LingFeng.OA.Model;

namespace LingFeng.OA.IDal
{
    <#
    foreach (var entity in typeMapper.GetItemsToGenerate<EntityType>(itemCollection))
    {#> 
        public partial interface I<#=string.Concat(entity.Name.First<char>().ToString().ToUpper(),entity.Name.Substring(1))#>Dal: IBaseDal<<#=entity.Name#>>
        {

        }<#
    }#>

}
<#+

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<{0}>", GetTypeName(collectionType.TypeUsage, modelNamespace));
        }

        var typeName = _code.Escape(edmType.MetadataProperties
                                .Where(p => p.Name == ExternalTypeNameAttributeName)
                                .Select(p => (string)p.Value)
                                .FirstOrDefault())
            ?? (modelNamespace != null && 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 && isNullable == true ?
                String.Format(CultureInfo.InvariantCulture, "Nullable<{0}>", 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<MetadataItem>();
    }
    
    public bool EnumIsFlags(EdmType enumType)
    {
        ArgumentNotNull(enumType, "enumType");
        
        var isFlagsProperty = enumType.GetType().GetProperty("IsFlags");
        return isFlagsProperty != null && (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<string> types, string sourceFile)
    {
        ArgumentNotNull(types, "types");
        ArgumentNotNull(sourceFile, "sourceFile");
        
        var hash = new HashSet<string>(StringComparer.InvariantCultureIgnoreCase);
        if (types.Any(item => !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<SimpleType> GetEnumItemsToGenerate(IEnumerable<GlobalItem> itemCollection)
    {
        return GetItemsToGenerate<SimpleType>(itemCollection)
            .Where(e => IsEnumType(e));
    }
    
    public IEnumerable<T> GetItemsToGenerate<T>(IEnumerable<GlobalItem> itemCollection) where T: EdmType
    {
        return itemCollection
            .OfType<T>()
            .Where(i => !i.MetadataProperties.Any(p => p.Name == ExternalTypeNameAttributeName))
            .OrderBy(i => i.Name);
    }

    public IEnumerable<string> GetAllGlobalItems(IEnumerable<GlobalItem> itemCollection)
    {
        return itemCollection
            .Where(i => i is EntityType || i is ComplexType || i is EntityContainer || IsEnumType(i))
            .Select(g => GetGlobalItemName(g));
    }

    public string GetGlobalItemName(GlobalItem item)
    {
        if (item is EdmType)
        {
            return ((EdmType)item).Name;
        }
        else
        {
            return ((EntityContainer)item).Name;
        }
    }

    public IEnumerable<EdmProperty> GetSimpleProperties(EntityType type)
    {
        return type.Properties.Where(p => p.TypeUsage.EdmType is SimpleType && p.DeclaringType == type);
    }
    
    public IEnumerable<EdmProperty> GetSimpleProperties(ComplexType type)
    {
        return type.Properties.Where(p => p.TypeUsage.EdmType is SimpleType && p.DeclaringType == type);
    }
    
    public IEnumerable<EdmProperty> GetComplexProperties(EntityType type)
    {
        return type.Properties.Where(p => p.TypeUsage.EdmType is ComplexType && p.DeclaringType == type);
    }
    
    public IEnumerable<EdmProperty> GetComplexProperties(ComplexType type)
    {
        return type.Properties.Where(p => p.TypeUsage.EdmType is ComplexType && p.DeclaringType == type);
    }

    public IEnumerable<EdmProperty> GetPropertiesWithDefaultValues(EntityType type)
    {
        return type.Properties.Where(p => p.TypeUsage.EdmType is SimpleType && p.DeclaringType == type && p.DefaultValue != null);
    }
    
    public IEnumerable<EdmProperty> GetPropertiesWithDefaultValues(ComplexType type)
    {
        return type.Properties.Where(p => p.TypeUsage.EdmType is SimpleType && p.DeclaringType == type && p.DefaultValue != null);
    }

    public IEnumerable<NavigationProperty> GetNavigationProperties(EntityType type)
    {
        return type.NavigationProperties.Where(np => np.DeclaringType == type);
    }
    
    public IEnumerable<NavigationProperty> GetCollectionNavigationProperties(EntityType type)
    {
        return type.NavigationProperties.Where(np => np.DeclaringType == type && np.ToEndMember.RelationshipMultiplicity == RelationshipMultiplicity.Many);
    }
    
    public FunctionParameter GetReturnParameter(EdmFunction edmFunction)
    {
        ArgumentNotNull(edmFunction, "edmFunction");

        var returnParamsProperty = edmFunction.GetType().GetProperty("ReturnParameters");
        return returnParamsProperty == null
            ? edmFunction.ReturnParameter
            : ((IEnumerable<FunctionParameter>)returnParamsProperty.GetValue(edmFunction, null)).FirstOrDefault();
    }

    public bool IsComposable(EdmFunction edmFunction)
    {
        ArgumentNotNull(edmFunction, "edmFunction");

        var isComposableProperty = edmFunction.GetType().GetProperty("IsComposableAttribute");
        return isComposableProperty != null && (bool)isComposableProperty.GetValue(edmFunction, null);
    }

    public IEnumerable<FunctionImportParameter> GetParameters(EdmFunction edmFunction)
    {
        return FunctionImportParameter.Create(edmFunction.Parameters, _code, _ef);
    }

    public TypeUsage GetReturnType(EdmFunction edmFunction)
    {
        var returnParam = GetReturnParameter(edmFunction);
        return returnParam == null ? null : _ef.GetElementType(returnParam.TypeUsage);
    }
    
    public bool GenerateMergeOptionFunction(EdmFunction edmFunction, bool includeMergeOption)
    {
        var returnType = GetReturnType(edmFunction);
        return !includeMergeOption && returnType != null && returnType.EdmType.BuiltInTypeKind == BuiltInTypeKind.EntityType;
    }
}

public static void ArgumentNotNull<T>(T arg, string name) where T : class
{
    if (arg == null)
    {
        throw new ArgumentNullException(name);
    }
}
#>