直接上方法，看的懂的拿去用，看不懂的找资料看懂

public PartialViewResult _Product(int pageindex = 1, int pagesize = 12, Double floorprice = 0, Double topprice = 9999999999, string brandstr = "", string categorystr = "", string orderBy = "priceasc") {            int[] brands;            if (string.IsNullOrWhiteSpace(brandstr)) {                brands = null;            }            else {                brands = Array.ConvertAll
     
      (brandstr.Split(','), delegate(string s) { return int.Parse(s); });            }            int[] categorys;            if (string.IsNullOrWhiteSpace(categorystr)) {                categorys = null;            }            else {                categorys = Array.ConvertAll
      
       (categorystr.Split(','), delegate(string s) { return int.Parse(s); });            }            IEnumerable
       
         product;            ParameterExpression paramExpr = Expression.Parameter(typeof(Product), "it");            MemberExpression floorpricePropExpr = Expression.Property(paramExpr, "UnitPrice");            ConstantExpression floorpriceValueExpr = Expression.Constant(floorprice, typeof(Double));            BinaryExpression floorpriceExpr = Expression.GreaterThanOrEqual(floorpricePropExpr, floorpriceValueExpr);            //出自http://www.cnblogs.com/ahjesus 尊重作者辛苦劳动成果,转载请注明出处,谢谢!            MemberExpression toppricePropExpr = Expression.Property(paramExpr, "UnitPrice");            ConstantExpression toppriceValueExpr = Expression.Constant(topprice, typeof(Double));            BinaryExpression toppriceExpr = Expression.LessThanOrEqual(toppricePropExpr, toppriceValueExpr);            Expression whereExpr = Expression.And(floorpriceExpr, toppriceExpr);            Expression whereBrandExpr = null;            if (brands != null && brands.Length > 0) {                for (int i = 0, j = brands.Length; i < j; i++) {                    int brand = brands[i];                    MemberExpression BrandPropExpr = Expression.Property(paramExpr, "Brand");                    ConstantExpression BrandValueExpr = Expression.Constant(brand, typeof(int));                    BinaryExpression BrandExpr = Expression.Equal(BrandPropExpr, BrandValueExpr);                    if (i == 0) {                        whereBrandExpr = BrandExpr;                    }                    else { whereBrandExpr = Expression.Or(whereBrandExpr, BrandExpr); }                }            }            Expression wherecategoryExpr = null;            if (categorys != null && categorys.Length > 0) {                for (int i = 0, j = categorys.Length; i < j; i++) {                    int category = categorys[i];                    MemberExpression categoryPropExpr = Expression.Property(paramExpr, "Category");                    ConstantExpression categoryValueExpr = Expression.Constant(category, typeof(int));                    BinaryExpression categoryExpr = Expression.Equal(categoryPropExpr, categoryValueExpr);                    if (wherecategoryExpr == null) {                        if (i == 0) {                            wherecategoryExpr = categoryExpr;                        }//出自http://www.cnblogs.com/ahjesus 尊重作者辛苦劳动成果,转载请注明出处,谢谢!                        else {                            wherecategoryExpr = Expression.Or(wherecategoryExpr, categoryExpr);                        }                    }                    else {                        wherecategoryExpr = Expression.Or(wherecategoryExpr, categoryExpr);                    }                }            }            if (whereBrandExpr != null) {                whereExpr = Expression.And(whereExpr, whereBrandExpr);            }            if (wherecategoryExpr != null) {                whereExpr = Expression.And(whereExpr, wherecategoryExpr);            }            Expression
        
         
          > lambda = Expression.Lambda
          
           
            >(whereExpr, paramExpr); switch (orderBy) { case "priceasc": product = BLLRequest.Current.ProductCollection.Where(lambda.Compile()).OrderBy(it => it.UnitPrice); break; case "pricedesc": product = BLLRequest.Current.ProductCollection.Where(lambda.Compile()).OrderByDescending(it => it.UnitPrice); break; case "salesasc": product = BLLRequest.Current.ProductCollection.Where(lambda.Compile()).OrderBy(it => it.SalesQty); break; case "salesdesc": product = BLLRequest.Current.ProductCollection.Where(lambda.Compile()).OrderByDescending(it => it.SalesQty); break; default: product = BLLRequest.Current.ProductCollection.Where(lambda.Compile()).OrderBy(it => it.UnitPrice); break; } int total = product.Count(); int pagecount = (total % pagesize) > 0 ? (total / pagesize) + 1 : (total / pagesize); product = product.Skip((pageindex - 1) * pagesize).Take(pagesize); ViewBag.product = product; ViewBag.total = total; ViewBag.pagecount = pagecount; ViewBag.pageindex = pageindex; return PartialView(); }