t4 - 读取t4模板中命名空间中的类

Question

有没有一种方法可以读取 namespace 并使用反射或其他方法遍历t4模板中的所有类？

<#foreach (class poco in LoadNamespace("Web.Code.Entities.Poco").Classes ) { #>
public interface I<# poco.ClassName #>Repository 
{
    IQueryable< <# poco.ClassName #> > Get();
    <# poco.ClassName #> Save(<# poco.ClassName #> entity);
    bool Delete(<# poco.ClassName #> entity);
}
<#} #>

元数据示例:

namespace Web.Code.Entities.Poco
{
    public class Product
    { 
          public int Id { get; set; }
          public string Name{ get; set; }
          public string Category{ get; set; }
    }

    public class Employee
    { 
          public int Id { get; set; }
          public string Name{ get; set; } 
    }
}

所需的输出:

    public interface IProductRepository 
    {
        IQueryable<Product> Get();
        Product Save(Product entity);
        bool Delete(Product entity);
    }   

    public interface IEmployeeRepository 
    {
        IQueryable<Employee> Get();
        Employee Save(Employee entity);
        bool Delete(Employee entity);
    }

Answer 1

首先安装T4Toolbox from here

然后在您的模板中确保顶部有以下几行:

<#@ assembly name="EnvDTE" #> 
<#@ import namespace="EnvDTE" #>
<#@ include file="T4Toolbox.tt" #>

然后添加以下代码行:

<#+  

private List<CodeClass> FindClasses(string nameSpace, string className)
{
    List<CodeClass> result=new List<CodeClass>();
    FindClasses(TransformationContext.Project.CodeModel.CodeElements,className,nameSpace,result,false);
    return result;

}


private void FindClasses(CodeElements elements, string className,string searchNamespace,List<CodeClass> result,bool isNamespaceOk)
{
    if (elements==null)return;
    foreach (CodeElement element in elements)
    {       
        if(element is CodeNamespace)
        {
            CodeNamespace ns = element as CodeNamespace;
            if(ns != null)
            {
                if (ns.FullName == searchNamespace)
                    FindClasses(ns.Members, className,searchNamespace,result,true);
                else
                    FindClasses(ns.Members, className,searchNamespace,result,false);
            }
        }
        else if(element is CodeClass && isNamespaceOk)
        {
            CodeClass c = element as CodeClass;
            if (c != null)
            {
                if(c.FullName.Contains(className))
                    result.Add(c);

                FindClasses(c.Members, className,searchNamespace,result,true);
            }

        }
    }
}
#>

然后，您可以通过这样调用来在 namespace 中找到所有类(第二个参数过滤名称包含传递的字符串的所有类):

FindClasses("NameSpace.SubNameSpace",""))//All classes in the specifed namespace 

或者

FindClasses("NameSpace.SubNameSpace","Repository")) //All classes in the specifed namespace which have "Repository" in their names

------------------------------------------ VS 2012的更新--- -----------------------

如果您的T4Toolbox已针对VS 2012更新，请使用以下函数和 namespace :

//visual studio 2012+
<#@ assembly name="Microsoft.VisualStudio.Shell.11.0" #>
<#@ assembly name="Microsoft.VisualStudio.Shell.Interop" #>
<#@ import namespace="Microsoft.VisualStudio.Shell" #>
<#@ import namespace="Microsoft.VisualStudio.Shell.Interop" #>

private List<CodeClass> FindClasses(string nameSpace, string className,string baseClassName)
{
    List<CodeClass> result=new List<CodeClass>();
    FindClasses(GetProject().CodeModel.CodeElements,className,baseClassName,nameSpace,result,false);
    return result;

}


private void FindClasses(CodeElements elements, string className,string baseClassName,string searchNamespace,List<CodeClass> result,bool isNamespaceOk)
{
    if (elements==null)return;
    foreach (CodeElement element in elements)
    {       
        if(element is CodeNamespace)
        {
            CodeNamespace ns = element as CodeNamespace;
            if(ns != null)
            {
                if (ns.FullName == searchNamespace)
                    FindClasses(ns.Members, className,baseClassName,searchNamespace,result,true);
                else
                    FindClasses(ns.Members, className,baseClassName,searchNamespace,result,false);
            }
        }
        else if(element is CodeClass && isNamespaceOk)
        {
            CodeClass c = element as CodeClass;
            if (c != null)
            {
                if(c.FullName.Contains(className) && (baseClassName==null || (HasIt(c.Bases ,baseClassName) && c.Name != baseClassName)))
                    result.Add(c);

                FindClasses(c.Members, className,baseClassName,searchNamespace,result,true);
            }

        }
    }
}

private bool HasIt(CodeElements elements,string name)
{
    foreach (CodeElement element in elements)
    {
        if (element.Name==name)
            return true;
    }
    return false;
}

private Project GetProject()
{
    // Get DTE
    var dte = (DTE)TransformationContext.Current.GetService(typeof(DTE));

    // Get ProjectItem representing the template file
    ProjectItem projectItem = dte.Solution.FindProjectItem(TransformationContext.Current.Host.TemplateFile);

    // Get the Project of the template file
    Project project = projectItem.ContainingProject;

    return project;
}

private string GetDefaultNamespace()
{

    // Get DTE
    var dte = (DTE)TransformationContext.Current.GetService(typeof(DTE));

    // Get ProjectItem representing the template file
    ProjectItem projectItem = dte.Solution.FindProjectItem(TransformationContext.Current.Host.TemplateFile);

    // Get the Project of the template file
    Project project = projectItem.ContainingProject;

    var vsSolution = (IVsSolution)TransformationContext.Current.GetService(typeof(SVsSolution));
    IVsHierarchy vsHierarchy;
    ErrorHandler.ThrowOnFailure(vsSolution.GetProjectOfUniqueName(project.FullName, out vsHierarchy));
    uint projectItemId;
    ErrorHandler.ThrowOnFailure(vsHierarchy.ParseCanonicalName(projectItem.FileNames[1], out projectItemId));
    object defaultNamespace;
    ErrorHandler.ThrowOnFailure(vsHierarchy.GetProperty(projectItemId, (int)VsHierarchyPropID.DefaultNamespace, out defaultNamespace));
    return ((string)defaultNamespace);
}

因此您的搜索将如下所示:

FindClasses(GetDefaultNamespace(),"Repository","RepositoryBase")