/// <summary>
/// 只适用于EF框架
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="expression"></param>
/// <param name="desc"></param>
/// <returns></returns>
private Pagination OrderBy <T>(Expression <Func <T, object> >[] expression, bool desc)
{
foreach (var item in expression)
{
MemberExpression mexp = null;
if (item.Body.NodeType == ExpressionType.Convert)
{
var temp = (UnaryExpression)item.Body;
if (temp.Operand.NodeType == ExpressionType.MemberAccess)
{
mexp = (MemberExpression)temp.Operand;
}
}
else
{
mexp = item.Body as MemberExpression;
}
if (mexp != null && mexp.Member != null)
{
var s = string.Format("{0} {1}", mexp.Member.Name, desc ? "desc" : "asc");
SortExpress.Add(s);
}
else
{
throw new ArgumentException("没有找到合适的属性");
}
}
return(this);
}
/// <summary>
/// 排序，只适用于EF框架
/// </summary>
/// <param name="expression"></param>
/// <param name="desc"></param>
/// <returns></returns>
public Pagination OrderBy(string expression, bool desc)
{
//SortExpress = new List<string>() { expression + (desc ? " desc" : " asc") };
if (SortExpress == null)
{
SortExpress = new List <string>();
}
SortExpress.Add(expression + " desc");
return(this);
}
/// <summary>
/// 按照指定字段排序，如果字段已经存在排序表达式中，则逆反排序方向,只适用Linq
/// </summary>
/// <param name="expression">排序字段</param>
/// <returns></returns>
public Pagination OrderBy(string expression)
{
//var item = SortExpress.Select( c=>c.Trim().Split(' ')).Where( c=>c[0] == expression).FirstOrDefault();
//bool desc = false;
//if (item != null)
//{
// desc = item[1] != "desc";
//}
//SortExpress = new List<string>() { expression + (desc ? " desc" : " asc") };
if (SortExpress == null)
{
SortExpress = new List <string>();
}
SortExpress.Add(expression + " asc");
return(this);
}
