CNCEC_SUBQHSE_WUHUAN/SGGL/BLL/SortConditionHelper.cs

38 lines
1.6 KiB
C#

using System;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
namespace BLL
{
public static class SortConditionHelper
{
public static IQueryable<T> DataSorting<T>(IQueryable<T> source, string sortExpression, string sortDirection)
{
string sortingDir = string.Empty;
if (sortDirection.ToUpper().Trim() == "ASC")
sortingDir = " OrderBy ";
else if (sortDirection.ToUpper().Trim() == "DESC")
sortingDir = " OrderByDescending ";
ParameterExpression param = Expression.Parameter(typeof(T), sortExpression);
PropertyInfo pi = typeof(T).GetProperty(sortExpression);
Type[] types = new Type[2];
types[0] = typeof(T);
types[1] = pi.PropertyType;
Expression expr = Expression.Call(typeof(Queryable), sortingDir, types, source.Expression, Expression.Lambda(Expression.Property(param, sortExpression), param));
IQueryable<T> query = source.AsQueryable().Provider.CreateQuery<T>(expr);
return query;
}
public static IQueryable<T> DataPaging<T>(IQueryable<T> source, int pageNumber, int pageSize)
{
return source.Skip(pageNumber * pageSize).Take(pageSize);
}
public static IQueryable<T> SortingAndPaging<T>(IQueryable<T> source, string sortExpression, string sortDirection, int pageNumber, int pageSize)
{
IQueryable<T> query = DataSorting<T>(source, sortExpression, sortDirection);
return DataPaging(query, pageNumber, pageSize);
}
}
}