/// <summary>
/// 向原始查询附加额外的查询条件。
/// </summary>
/// <typeparam name="TOriginalElementType">query 查询的原始元素类型</typeparam>
/// <param name="source">一个原始查询的数据源。</param>
/// <param name="query">需要附加的查询条件。</param>
/// <returns>附加完毕查询的数据源。</returns>
public static IQueryable Attach <TOriginalElementType>(this IQueryable source, IQueryable query)
{
var attacher = new ExpressionAttacher();
attacher.DataSource = source;
var parser = attacher.Attach(typeof(TOriginalElementType), query.Expression);
return(parser.DataSource);
}
public object Execute(Expression expression)
{
var attacher = new ExpressionAttacher
{
DataSource = DataSource()
};
var parser = attacher.Attach(OriginalElementType, expression);
return(parser.Value);
}
/// <summary>
/// 向原始查询附加额外的查询条件。
/// </summary>
/// <param name="source">一个原始查询的数据源。</param>
/// <param name="query">需要附加的查询条件：ConvertQueryable 类型。</param>
/// <returns>附加完毕查询的数据源。</returns>
public static IQueryable Attach(this IQueryable source, IQueryable query)
{
if (!(query is IElementTypeProvider))
{
throw new ArgumentException("The query is not ConvertQueryable<T> type.");
}
var attacher = new ExpressionAttacher();
attacher.DataSource = source;
var parser = attacher.Attach((query as IElementTypeProvider).OriginalElementType, query.Expression);
return(parser.DataSource);
}