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//------------------------------------------------------------------------------
// <copyright file="DbCommandDefinition.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft
// @backupOwner Microsoft
//------------------------------------------------------------------------------
using System.Diagnostics;
using System.Data.Metadata.Edm;
namespace System.Data.Common {
/// <summary>
/// A prepared command definition, can be cached and reused to avoid
/// repreparing a command.
/// </summary>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1709:IdentifiersShouldBeCasedCorrectly", MessageId = "Db")]
public class DbCommandDefinition {
private readonly ICloneable _prototype;
/// <summary>
/// Internal factory method to create the default Command Definition object
/// based on a prototype command. The prototype command is cloned
/// before the protected constructor is invoked
/// </summary>
/// <param name="prototype">prototype DbCommand</param>
/// <returns>the DbCommandDefinition</returns>
internal static DbCommandDefinition CreateCommandDefinition(DbCommand prototype) {
EntityUtil.CheckArgumentNull(prototype, "prototype");
ICloneable cloneablePrototype = prototype as ICloneable;
if (null == cloneablePrototype) {
throw EntityUtil.CannotCloneStoreProvider();
}
DbCommand clonedPrototype = (DbCommand)(cloneablePrototype.Clone());
return new DbCommandDefinition(clonedPrototype);
}
/// <summary>
/// Protected constructor; the command is assumed to be a prototype
/// that will be cloned on CreateCommand, and the cloned command will be executed.
/// </summary>
protected DbCommandDefinition(DbCommand prototype) {
EntityUtil.CheckArgumentNull(prototype, "prototype");
_prototype = prototype as ICloneable;
if (null == _prototype) {
throw EntityUtil.CannotCloneStoreProvider();
}
}
/// <summary>
/// Constructor overload for subclasses to use
/// </summary>
protected DbCommandDefinition() {
}
/// <summary>
/// Create a DbCommand object from the definition, that can be executed.
/// </summary>
/// <returns></returns>
public virtual DbCommand CreateCommand() {
return (DbCommand)(_prototype.Clone());
}
internal static void PopulateParameterFromTypeUsage(DbParameter parameter, TypeUsage type, bool isOutParam)
{
EntityUtil.CheckArgumentNull(parameter, "parameter");
EntityUtil.CheckArgumentNull(type, "type");
// parameter.IsNullable - from the NullableConstraintAttribute value
parameter.IsNullable = TypeSemantics.IsNullable(type);
// parameter.ParameterName - set by the caller;
// parameter.SourceColumn - not applicable until we have a data adapter;
// parameter.SourceColumnNullMapping - not applicable until we have a data adapter;
// parameter.SourceVersion - not applicable until we have a data adapter;
// parameter.Value - left unset;
// parameter.DbType - determined by the TypeMapping;
// parameter.Precision - from the TypeMapping;
// parameter.Scale - from the TypeMapping;
// parameter.Size - from the TypeMapping;
// type.EdmType may not be a primitive type here - e.g. the user specified
// a complex or entity type when creating an ObjectParameter instance. To keep
// the same behavior we had in previous versions we let it through here. We will
// throw an exception later when actually invoking the stored procedure where we
// don't allow parameters that are non-primitive.
if(Helper.IsPrimitiveType(type.EdmType))
{
DbType dbType;
if (TryGetDbTypeFromPrimitiveType((PrimitiveType)type.EdmType, out dbType))
{
switch (dbType)
{
case DbType.Binary:
PopulateBinaryParameter(parameter, type, dbType, isOutParam);
break;
case DbType.DateTime:
case DbType.Time:
case DbType.DateTimeOffset:
PopulateDateTimeParameter(parameter, type, dbType);
break;
case DbType.Decimal:
PopulateDecimalParameter(parameter, type, dbType);
break;
case DbType.String:
PopulateStringParameter(parameter, type, isOutParam);
break;
default:
parameter.DbType = dbType;
break;
}
}
}
}
internal static bool TryGetDbTypeFromPrimitiveType(PrimitiveType type, out DbType dbType)
{
switch (type.PrimitiveTypeKind)
{
case PrimitiveTypeKind.Binary:
dbType = DbType.Binary;
return true;
case PrimitiveTypeKind.Boolean:
dbType = DbType.Boolean;
return true;
case PrimitiveTypeKind.Byte:
dbType = DbType.Byte;
return true;
case PrimitiveTypeKind.DateTime:
dbType = DbType.DateTime;
return true;
case PrimitiveTypeKind.Time:
dbType = DbType.Time;
return true;
case PrimitiveTypeKind.DateTimeOffset:
dbType = DbType.DateTimeOffset;
return true;
case PrimitiveTypeKind.Decimal:
dbType = DbType.Decimal;
return true;
case PrimitiveTypeKind.Double:
dbType = DbType.Double;
return true;
case PrimitiveTypeKind.Guid:
dbType = DbType.Guid;
return true;
case PrimitiveTypeKind.Single:
dbType = DbType.Single;
return true;
case PrimitiveTypeKind.SByte:
dbType = DbType.SByte;
return true;
case PrimitiveTypeKind.Int16:
dbType = DbType.Int16;
return true;
case PrimitiveTypeKind.Int32:
dbType = DbType.Int32;
return true;
case PrimitiveTypeKind.Int64:
dbType = DbType.Int64;
return true;
case PrimitiveTypeKind.String:
dbType = DbType.String;
return true;
default:
dbType = default(DbType);
return false;
}
}
private static void PopulateBinaryParameter(DbParameter parameter, TypeUsage type, DbType dbType, bool isOutParam)
{
parameter.DbType = dbType;
// For each facet, set the facet value only if we have it, note that it's possible to not have
// it in the case the facet value is null
SetParameterSize(parameter, type, isOutParam);
}
private static void PopulateDecimalParameter (DbParameter parameter, TypeUsage type, DbType dbType)
{
parameter.DbType = dbType;
IDbDataParameter dataParameter = (IDbDataParameter)parameter;
// For each facet, set the facet value only if we have it, note that it's possible to not have
// it in the case the facet value is null
byte precision;
byte scale;
if (TypeHelpers.TryGetPrecision(type, out precision))
{
dataParameter.Precision = precision;
}
if (TypeHelpers.TryGetScale(type, out scale))
{
dataParameter.Scale = scale;
}
}
private static void PopulateDateTimeParameter(DbParameter parameter, TypeUsage type, DbType dbType)
{
parameter.DbType = dbType;
IDbDataParameter dataParameter = (IDbDataParameter)parameter;
// For each facet, set the facet value only if we have it, note that it's possible to not have
// it in the case the facet value is null
byte precision;
if (TypeHelpers.TryGetPrecision(type, out precision))
{
dataParameter.Precision = precision;
}
}
private static void PopulateStringParameter(DbParameter parameter, TypeUsage type, bool isOutParam)
{
// For each facet, set the facet value only if we have it, note that it's possible to not have
// it in the case the facet value is null
bool unicode = true;
bool fixedLength = false;
if (!TypeHelpers.TryGetIsFixedLength(type, out fixedLength))
{
// If we can't get the fixed length facet value, then default to fixed length = false
fixedLength = false;
}
if (!TypeHelpers.TryGetIsUnicode(type, out unicode))
{
// If we can't get the unicode facet value, then default to unicode = true
unicode = true;
}
if (fixedLength)
{
parameter.DbType = (unicode ? DbType.StringFixedLength : DbType.AnsiStringFixedLength);
}
else
{
parameter.DbType = (unicode ? DbType.String : DbType.AnsiString);
}
SetParameterSize(parameter, type, isOutParam);
}
private static void SetParameterSize(DbParameter parameter, TypeUsage type, bool isOutParam)
{
// only set the size if the parameter has a specific size value.
Facet maxLengthFacet;
if (type.Facets.TryGetValue(DbProviderManifest.MaxLengthFacetName, true, out maxLengthFacet) && maxLengthFacet.Value != null)
{
// only set size if there is a specific size
if (!Helper.IsUnboundedFacetValue(maxLengthFacet))
{
parameter.Size = (int)maxLengthFacet.Value;
}
else if (isOutParam)
{
// if it is store procedure parameter and it is unbounded set the size to max
parameter.Size = Int32.MaxValue;
}
}
}
}
}
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