EntityFramework4的POCO模板生成FunctionImport返回空的服务端调用代码
我们知道Entity Framework 4 默认根据MODEL生成ServerCode, 现在我们使用POCO T4模板。有个小问题，对于那些Function Import的存储过程没有返回值，却没有生成相应的CODE。主要生成于一个DataContext下，通常是XXXXX.Context.tt的模板。打开模板，你可以找到这么一行代码：
if (edmFunction.ReturnParameter == null)
就是这里了，接下我们自己来修改一下。最后修改完后，如下：
<#
//*********************************************************
//
// Copyright (c) Microsoft. All rights reserved.
// This code is licensed under the Microsoft Public License.
// THIS CODE IS PROVIDED *AS IS* WITHOUT WARRANTY OF
// ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING ANY
// IMPLIED WARRANTIES OF FITNESS FOR A PARTICULAR
// PURPOSE, MERCHANTABILITY, OR NON-INFRINGEMENT.
//
//*********************************************************
#>
<#@ template language="C#" debug="false" hostspecific="true"#>
<#@ include file="EF.Utility.CS.ttinclude"#><#@
output extension=".cs"#><#
CodeGenerationTools code = new CodeGenerationTools(this);
MetadataTools ef = new MetadataTools(this);
MetadataLoader loader = new MetadataLoader(this);
CodeRegion region = new CodeRegion(this);
string inputFile = @"model.edmx";
EdmItemCollection ItemCollection = loader.CreateEdmItemCollection(inputFile);
string namespaceName = code.VsNamespaceSuggestion();
EntityContainer container = ItemCollection.GetItems<EntityContainer>().FirstOrDefault();
if (container == null)
{
return "// No EntityContainer exists in the model, so no code was generated";
}
#>
//------------------------------------------------------------------------------
// <auto-generated>
// This code was generated from a template.
//
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
using System;
using System.Data.Objects;
using System.Data.EntityClient;
<#
if (!String.IsNullOrEmpty(namespaceName))
{
#>
namespace <#=code.EscapeNamespace(namespaceName)#>
{
<#
PushIndent(CodeRegion.GetIndent(1));
}
#>
<#=Accessibility.ForType(container)#> partial class <#=code.Escape(container)#> : ObjectContext
{
public const string ConnectionString = "name=<#=container.Name#>";
public const string ContainerName = "<#=container.Name#>";
#region Constructors
public <#=code.Escape(container)#>()
: base(ConnectionString, ContainerName)
{
<#
WriteLazyLoadingEnabled(container);
#>
}
public <#=code.Escape(container)#>(string connectionString)
: base(connectionString, ContainerName)
{
<#
WriteLazyLoadingEnabled(container);
#>
}
public <#=code.Escape(container)#>(EntityConnection connection)
: base(connection, ContainerName)
{
<#
WriteLazyLoadingEnabled(container);
#>
}
#endregion
<#
region.Begin("ObjectSet Properties", 2);
foreach (EntitySet entitySet in container.BaseEntitySets.OfType<EntitySet>())
{
#>
<#=Accessibility.ForReadOnlyProperty(entitySet)#> ObjectSet<<#=code.Escape(entitySet.ElementType)#>> <#=code.Escape(entitySet)#>
{
get { return <#=code.FieldName(entitySet) #> ?? (<#=code.FieldName(entitySet)#> = CreateObjectSet<<#=code.Escape(entitySet.ElementType)#>>("<#=entitySet.Name#>")); }
}
private ObjectSet<<#=code.Escape(entitySet.ElementType)#>> <#=code.FieldName(entitySet)#>;
<#
}
region.End();
region.Begin("Function Imports");
foreach (EdmFunction edmFunction in container.FunctionImports)
{
var parameters = FunctionImportParameter.Create(edmFunction.Parameters, code, ef);
string paramList = String.Join(", ", parameters.Select(p => p.FunctionParameterType + " " + p.FunctionParameterName).ToArray());
string returnTypeElement = "int";
if (edmFunction.ReturnParameter == null)
{
#>
<#=Accessibility.ForMethod(edmFunction)#> void <#=code.Escape(edmFunction)#>(<#=paramList#>)
{
<#
}
else
{
returnTypeElement = code.Escape(ef.GetElementType(edmFunction.ReturnParameter.TypeUsage));
#>
<#=Accessibility.ForMethod(edmFunction)#> ObjectResult<<#=returnTypeElement#>> <#=code.Escape(edmFunction)#>(<#=paramList#>)
{
<#
}
foreach (var parameter in parameters)
{
if (!parameter.NeedsLocalVariable)
{
continue;
}
#>
ObjectParameter <#=parameter.LocalVariableName#>;
if (<#=parameter.IsNullableOfT ? parameter.FunctionParameterName + ".HasValue" : parameter.FunctionParameterName + " != null"#>)
{
<#=parameter.LocalVariableName#> = new ObjectParameter("<#=parameter.EsqlParameterName#>", <#=parameter.FunctionParameterName#>);
}
else
{
<#=parameter.LocalVariableName#> = new ObjectParameter("<#=parameter.EsqlParameterName#>", typeof(<#=parameter.RawClrTypeName#>));
}
<#
}
if (edmFunction.ReturnParameter == null)
{
#>
base.ExecuteFunction("<#=edmFunction.Name#>"<#=code.StringBefore(", ", String.Join(", ", parameters.Select(p => p.ExecuteParameterName).ToArray()))#>);
}
<#
}
else
{
#>
return base.ExecuteFunction<<#=returnTypeElement#>>("<#=edmFunction.Name#>"<#=code.StringBefore(", ", String.Join(", ", parameters.Select(p => p.ExecuteParameterName).ToArray()))#>);
}
<#
}
}
region.End();
#>
}
<#
if (!String.IsNullOrEmpty(namespaceName))
{
PopIndent();
#>
}
<#
}
#>
<#+
private void WriteLazyLoadingEnabled(EntityContainer container)
{
string lazyLoadingAttributeValue = null;
string lazyLoadingAttributeName = MetadataConstants.EDM_ANNOTATION_09_02 + ":LazyLoadingEnabled";
if(MetadataTools.TryGetStringMetadataPropertySetting(container, lazyLoadingAttributeName, out lazyLoadingAttributeValue))
{
bool isLazyLoading = false;
if(bool.TryParse(lazyLoadingAttributeValue, out isLazyLoading))
{
#>
this.ContextOptions.LazyLoadingEnabled = <#=isLazyLoading.ToString().ToLowerInvariant()#>;
<#+
}
}
}
#>
把那个inputfile变量的值替换成你的edmx，就可以使用了。将生成这样的代码，注意这个方法返回是void:
1: public partial class Entities : ObjectContext
2: {
3:
4: public void ChangeForumID(string thread, Nullable<int> forum)
5: {
6: ObjectParameter threadParameter;
7: if (thread != null)
8: {
9: threadParameter = new ObjectParameter("Thread", thread);
10: }
11: else
12: {
13: threadParameter = new ObjectParameter("Thread", typeof(string));
14: }
15:
16: ObjectParameter forumParameter;
17: if (forum.HasValue)
18: {
19: forumParameter = new ObjectParameter("Forum", forum);
20: }
21: else
22: {
23: forumParameter = new ObjectParameter("Forum", typeof(int));
24: }
25:
26: base.ExecuteFunction("ChangeForumID", threadParameter, forumParameter);
27: }
28:
当然你手写也是可以的，不过数量多就很累了。希望这篇POST对您开发有帮助。
作者：Petter Liu
出处：http://www.cnblogs.com/wintersun/
本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。
该文章也同时发布在我的独立博客中-Petter Liu Blog。