Entity Framework4.1实现动态多条件查询、分页和排序

2、记录数///记录列表publicvirtualListGetMany(Expression>where,stringorderBy,boolascending,intpageIndex,intpageSize,outinttotalRecord){    totalRecord=0;    where=where.And(u=>u.Flag!=(int)Flags.Delete);    varlist=dbset.Where(where);      totalRecor

3、d=list.Count();    if(totalRecord<=0)returnnewList();      list=list.OrderBy(orderBy,ascending).Skip((pageIndex-1)*pageSize).Take(pageSize);      returnlist.ToList();} 动态排序扩展:+ViewCode?publicstaticIQueryableOrderBy(thisIQueryablesource,stringpropertyName,boolascending)w

4、hereT:class{    Typetype=typeof(T);      PropertyInfoproperty=type.GetProperty(propertyName);    if(property==null)        thrownewArgumentException("propertyName","NotExist");      ParameterExpressionparam=Expression.Parameter(type,"p");    ExpressionpropertyAccessExpression=Expre

5、ssion.MakeMemberAccess(param,property);    LambdaExpressionorderByExpression=Expression.Lambda(propertyAccessExpression,param);      stringmethodName=ascending?"OrderBy":"OrderByDescending";      MethodCallExpressionresultExp=Expression.Call(typeof(Queryable),methodName,newType[]{t

6、ype,property.PropertyType},source.Expression,Expression.Quote(orderByExpression));      returnsource.Provider.CreateQuery(resultExp);} 如果要通过Expression获取字段，可以使用以下代码:+ViewCode?///