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//---------------------------------------------------------------------
// <copyright file="Row.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
using System.Collections.Generic;
using System.Data.Common.CommandTrees;
using System.Data.Common.Utils;
namespace System.Data.Common.CommandTrees.ExpressionBuilder
{
/// <summary>
/// The Row class is intended to provide a constructor-like means of calling <see cref="DbExpressionBuilder.NewRow"/>.
/// </summary>
public sealed class Row
{
private readonly System.Collections.ObjectModel.ReadOnlyCollection<KeyValuePair<string, DbExpression>> arguments;
/// <summary>
/// Constructs a new Row with the specified first column value and optional successive column values
/// </summary>
/// <param name="columnValue">A key-value pair that provides the first column in the new row instance (required)</param>
/// <param name="columnValues">Key-value pairs that provide any subsequent columns in the new row instance (optional)</param>
public Row(KeyValuePair<string, DbExpression> columnValue, params KeyValuePair<string, DbExpression>[] columnValues)
{
this.arguments = new System.Collections.ObjectModel.ReadOnlyCollection<KeyValuePair<string, DbExpression>>(Helpers.Prepend(columnValues, columnValue));
}
/// <summary>
/// Creates a new <see cref="DbNewInstanceExpression"/> that constructs a new row based on the columns
/// contained in this Row instance.
/// </summary>
/// <returns>A new DbNewInstanceExpression that constructs a row with the same column names and DbExpression values as this Row instance</returns>
/// <seealso cref="DbExpressionBuilder.NewRow"/>
public DbNewInstanceExpression ToExpression()
{
return DbExpressionBuilder.NewRow(this.arguments);
}
/// <summary>
/// Converts the given Row instance into an instance of <see cref="DbExpression"/>
/// </summary>
/// <param name="row"></param>
/// <returns>A DbExpression based on the Row instance</returns>
/// <exception cref="ArgumentNullException"><paramref name="row"/> is null.</exception>
/// <seealso cref="ToExpression"/>
public static implicit operator DbExpression(Row row)
{
EntityUtil.CheckArgumentNull(row, "row");
return row.ToExpression();
}
}
}
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