从存储过程获取返回值

Question

I'm using Entity Framework 5 with the Code First approach. I need to read the return value from a stored procedure; I am already reading output parameters and sending input parameters, but I don't know how to read the return value.

Is it possible?

Here is the code that I use to call the stored procedure:

var outParam = new SqlParameter();
outParam.ParameterName = "@StatusLog";
outParam.SqlDbType = SqlDbType.NVarChar;
outParam.Size = 4000;
outParam.Direction = ParameterDirection.Output;

var code = new SqlParameter();
code.ParameterName = "@Code";
code.Direction = ParameterDirection.Input;
code.SqlDbType = SqlDbType.VarChar;
code.Size = 20;
code.Value = "123";

var data = _context.Database.SqlQuery<Item>("exec spItemData @Code, @StatusLog OUT", code, outParam);

var result = data.FirstOrDefault();

Answer 1

I found it! I can read the return value with an output parameter that has to be used in this way:

// define a new output parameter
var returnCode = new SqlParameter();
returnCode.ParameterName = "@ReturnCode";
returnCode.SqlDbType = SqlDbType.Int;
returnCode.Direction = ParameterDirection.Output;

// assign the return code to the new output parameter and pass it to the sp
var data = _context.Database.SqlQuery<Item>("exec @ReturnCode = spItemData @Code, @StatusLog OUT", returnCode, code, outParam);

Answer 2

The solution provided by Daniele wasn't working for me, until I found this blog post from Diego Vega , which explains that:

You will need to read the whole results before you can access the values of output parameters (...) This is just how stored procedures work and not specific to this EF feature.

Also, in my case, I wasn't returning an entity, I only had to execute the stored procedure, so I replaced Item with object in _context.Database.SqlQuery<object> .

Here is the sample code:

var code = new SqlParameter("@Code", 1);

var returnCode = new SqlParameter("@ReturnCode", SqlDbType.Int);
returnCode.Direction = ParameterDirection.Output;

var outParam = new SqlParameter("@StatusLog", SqlDbType.Int);
outParam.Direction = ParameterDirection.Output;

var sql = "exec @ReturnCode = spSomeRoutine @Code, @StatusLog OUT";
var data = _context.Database.SqlQuery<object>(sql, returnCode, code, outParam);

// Read the results so that the output variables are accessible
var item = data.FirstOrDefault();

var returnCodeValue = (int)returnCode.Value;
var outParamValue = (int)outParam.Value;

Here's a sample stored procedure:

CREATE PROCEDURE [dbo].[spSomeRoutine]
    @Code Int,
    @StatusLog INT OUTPUT
AS
BEGIN
    SET @StatusLog = 5
    RETURN 10
END

Answer 3

In the case where the stored proc does not have an output parameter I do the following, effectively making some Sql that returns a select statement;

var data = context.Database.SqlQuery<int>(@"declare @num int
exec  @num = myStoredProcThatReturnsInt 
select @num");

var result = data.First();

Answer 4

You can add the stored procedure as an EF function then call it driectly from the context.

See http://www.entityframeworktutorial.net/EntityFramework4.3/execute-stored-procedure-using-dbcontext.aspx

for more info

Answer 5

For anyone working with an EDMX file you can add a code generation item and then use the following t4 code to replace the .Context.tt. It will create all the code to map your stored procedures using the method:

var returnCode = new SqlParameter("@ReturnCode", SqlDbType.Int);
returnCode.Direction = ParameterDirection.Output;
var sql = "exec @ReturnCode = spSomeRoutine @Code, @StatusLog OUT";
var data = _context.Database.SqlQuery<object>(sql, returnCode, code, outParam);

It will use SqlQuery<> when there is a result set and ExecuteSqlCommand when there is not, but in both scenarios the out SqlParameter localSqlExecReturnValue will contain the int return code from the stored procedure call. This can be used with other generators it only generates additional code for stored procedure calls.

StoredProcedure.Context.tt:

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

const string inputFile = @"CDMSAccountingModel.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 loader = new EdmMetadataLoader(textTransform.Host, textTransform.Errors);
var itemCollection = loader.CreateEdmItemCollection(inputFile);
var modelNamespace = loader.GetModelNamespace(inputFile);
var codeStringGenerator = new CodeStringGenerator(code, typeMapper, ef);

var container = itemCollection.OfType<EntityContainer>().FirstOrDefault();
if (container == null)
{
    return string.Empty;
}
#>
//------------------------------------------------------------------------------
// <auto-generated>
// <#=CodeGenerationTools.GetResourceString("Template_GeneratedCodeCommentLine1")#>
//
// <#=CodeGenerationTools.GetResourceString("Template_GeneratedCodeCommentLine2")#>
// <#=CodeGenerationTools.GetResourceString("Template_GeneratedCodeCommentLine3")#>
// </auto-generated>
//------------------------------------------------------------------------------

<#

var codeNamespace = code.VsNamespaceSuggestion();
if (!String.IsNullOrEmpty(codeNamespace))
{
#>
namespace <#=code.EscapeNamespace(codeNamespace)#>
{
<#
    PushIndent("    ");
}

#>
using System;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
<#
if (container.FunctionImports.Any())
{
#>
using System.Data.Entity.Core.Objects;
using System.Linq;
<#
}
#>

<#=Accessibility.ForType(container)#> partial class <#=code.Escape(container)#> : DbContext
{

<#
foreach (var entitySet in container.BaseEntitySets.OfType<EntitySet>())
{
    // Note: the DbSet members are defined below such that the getter and
    // setter always have the same accessibility as the DbSet definition
    if (Accessibility.ForReadOnlyProperty(entitySet) != "public")
    {
#>
        <#=codeStringGenerator.DbSetInitializer(entitySet)#>
<#
    }
}
#>



<#
    foreach (var edmFunction in container.FunctionImports)
    {
        WriteFunctionImport(typeMapper, codeStringGenerator, edmFunction, modelNamespace, includeMergeOption: false);
    }
#>
}
<#

if (!String.IsNullOrEmpty(codeNamespace))
{
    PopIndent();
#>
}
<#
}
#>
<#+

private void WriteFunctionImport(TypeMapper typeMapper, CodeStringGenerator codeStringGenerator, EdmFunction edmFunction, string modelNamespace, bool includeMergeOption)
{
    if (typeMapper.IsComposable(edmFunction))
    {
#>

    [DbFunction("<#=edmFunction.NamespaceName#>", "<#=edmFunction.Name#>")]
    <#=codeStringGenerator.ComposableFunctionMethod(edmFunction, modelNamespace)#>
    {
<#+
        codeStringGenerator.WriteFunctionParameters(edmFunction, WriteFunctionParameter );
#>
        <#=codeStringGenerator.ComposableCreateQuery(edmFunction, modelNamespace)#>
    }
<#+
    }
    else
    {
#>

    <#=codeStringGenerator.FunctionMethod(edmFunction, modelNamespace, includeMergeOption)#>
    {
<#+
        codeStringGenerator.WriteFunctionParameters(edmFunction, WriteFunctionParameter);
#>
        localSqlExecReturnValue = new System.Data.SqlClient.SqlParameter("@localExecReturnValue",System.Data.SqlDbType.Int);
        localSqlExecReturnValue.Direction = System.Data.ParameterDirection.Output;

        <#=codeStringGenerator.ExecuteFunction(edmFunction, modelNamespace, includeMergeOption)#>
    }
<#+
        if (typeMapper.GenerateMergeOptionFunction(edmFunction, includeMergeOption))
        {
            WriteFunctionImport(typeMapper, codeStringGenerator, edmFunction, modelNamespace, includeMergeOption: true);
        }
    }
}

public void WriteFunctionParameter(string name, string isNotNull, string notNullInit, string nullInit)
{
#>
        var <#=name#> = <#=isNotNull#> ?
            <#=notNullInit#> :
            <#=nullInit#>;

<#+
}

public const string TemplateId = "CSharp_DbContext_Context_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<" + endType + ">") : 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<string, string, string, string> writeParameter)
    {
        var parameters = FunctionImportParameter.Create(edmFunction.Parameters, _code, _ef);
        foreach (var parameter in parameters.Where(p => p.NeedsLocalVariable))
        {
            var isNotNull = parameter.IsNullableOfT ? parameter.FunctionParameterName + ".HasValue" : parameter.FunctionParameterName + " != null";
            var notNullInit = "new System.Data.SqlClient.SqlParameter(\"@" + parameter.EsqlParameterName + "\", " + parameter.FunctionParameterName + ")";
            var nullInit = "new System.Data.SqlClient.SqlParameter(\"@" + parameter.EsqlParameterName + "\", SqlHelper.GetDbType(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<{1}> {2}({3})",
            AccessibilityAndVirtual(Accessibility.ForMethod(edmFunction)),
            _typeMapper.GetTypeName(_typeMapper.GetReturnType(edmFunction), modelNamespace),
            _code.Escape(edmFunction),
            string.Join(", ", parameters.Select(p => 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<{0}>(\"[{1}].[{2}]({3})\"{4});",
            _typeMapper.GetTypeName(_typeMapper.GetReturnType(edmFunction), modelNamespace),
            edmFunction.NamespaceName,
            edmFunction.Name,
            string.Join(", ", parameters.Select(p => "@" + p.EsqlParameterName).ToArray()),
            _code.StringBefore(", ", string.Join(", ", parameters.Select(p => 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 => TypeMapper.FixNamespaces(p.FunctionParameterType) + " " + p.FunctionParameterName).ToArray());
        paramList = String.Join(",", paramList, " out System.Data.SqlClient.SqlParameter localSqlExecReturnValue").Trim().TrimStart(',');
        paramList = paramList.Replace("ObjectParameter", "System.Data.SqlClient.SqlParameter");
        if (includeMergeOption)
        {
            paramList = _code.StringAfter(paramList, ", ") + "MergeOption mergeOption";
        }

        return string.Format(
            CultureInfo.InvariantCulture,
            "{0} {1} {2}({3})",
            AccessibilityAndVirtual(Accessibility.ForMethod(edmFunction)),
            returnType == null ? "int" : "System.Collections.Generic.List<" + _typeMapper.GetTypeName(returnType, modelNamespace) + ">",
            _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 =  String.Join(", ", parameters.Select(p => p.ExecuteParameterName).ToArray());
        callParams = _code.StringBefore(", ", String.Join(",", "localSqlExecReturnValue", callParams)).TrimEnd(',').Trim();

        var inSqlParams = String.Join(", ", parameters.Where(p => p.NeedsLocalVariable).Select(p => "@" + p.Source.Name).ToArray());
        var outSqlParams = String.Join(", ", parameters.Where(p => !p.NeedsLocalVariable).Select(p => "@" + p.Source.Name + " OUTPUT").ToArray());
        var sqlParams = "";
        if (inSqlParams.Count() > 0)
        {
            sqlParams = String.Join(", ", sqlParams, inSqlParams);
        }
        if (outSqlParams.Count() > 0)
        {
            sqlParams = String.Join(", ", sqlParams, outSqlParams);
        }
        sqlParams = sqlParams.Trim().Trim(',').Trim();
        if (includeMergeOption)
        {
            callParams = ", mergeOption" + callParams;
        }
        var retstring = string.Format(
            CultureInfo.InvariantCulture,
            "var results = {3}{0}(\"EXEC @localExecReturnValue = {1} {4}\"{2});",
            returnType == null ? "" : "<" + _typeMapper.GetTypeName(returnType, modelNamespace) + ">",
            edmFunction.Name,
            callParams,returnType != null ? "this.Database.SqlQuery" : "this.Database.ExecuteSqlCommand", sqlParams);
        retstring += Environment.NewLine;
        retstring += returnType != null ? "\t\treturn results.ToList();" : "\t\treturn results;";
        //retstring += Environment.NewLine + "\t\tlocalExecReturnValue = (int)localSqlExecReturnValue.Value;" ;
        //retstring += Environment.NewLine + "\t\treturn results;";
        return retstring;
    }

    public string DbSet(EntitySet entitySet)
    {
        return string.Format(
            CultureInfo.InvariantCulture,
            "{0} virtual DbSet<{1}> {2} {{ get; set; }}",
            Accessibility.ForReadOnlyProperty(entitySet),
            _typeMapper.GetTypeName(entitySet.ElementType),
            _code.Escape(entitySet));
    }

    public string DbSetInitializer(EntitySet entitySet)
    {
        return string.Format(
            CultureInfo.InvariantCulture,
            "{0} = Set<{1}>();",
            _code.Escape(entitySet),
            _typeMapper.GetTypeName(entitySet.ElementType));
    }

    public string UsingDirectives(bool inHeader, bool includeCollections = true)
    {
        return inHeader == string.IsNullOrEmpty(_code.VsNamespaceSuggestion())
            ? string.Format(
                CultureInfo.InvariantCulture,
                "{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 static string FixNamespaces(string typeName)
    {
        return typeName.Replace("System.Data.Spatial.", "System.Data.Entity.Spatial.");
    }

    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 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);
    }
}
#>