/// <summary>
/// 条件筛选 例如：expression 为 it=>it.a inValues值为 new string[]{"a" ,"b"} 生成的SQL就是 a in('a','b')
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="queryable"></param>
/// <param name="expression"></param>
/// <returns></returns>
public static Queryable <T> In <T, FieldType>(this Queryable <T> queryable, Expression <Func <T, object> > expression, params FieldType[] inValues)
{
ResolveExpress re = new ResolveExpress();
var InFieldName = re.GetExpressionRightFiled(expression);
return(In <T, FieldType>(queryable, InFieldName, inValues));
}
/// <summary>
/// 获取最小值
/// </summary>
/// <typeparam name="TResult"></typeparam>
/// <typeparam name="T"></typeparam>
/// <param name="queryable"></param>
/// <param name="minField">列</param>
/// <returns></returns>
public static object Min <T>(this Queryable <T> queryable, Expression <Func <T, object> > expression)
{
ResolveExpress re = new ResolveExpress();
var minField = re.GetExpressionRightFiled(expression);
return(Min <T, object>(queryable, minField));
}
/// <summary>
/// 分组
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="queryable"></param>
/// <param name="groupFileds">如：id,name </param>
/// <returns></returns>
public static Queryable <T> GroupBy <T>(this Queryable <T> queryable, Expression <Func <T, object> > expression)
{
ResolveExpress re = new ResolveExpress();
var field = re.GetExpressionRightFiled(expression);
var pre = queryable.GroupBy.IsValuable() ? "," : "";
queryable.GroupBy += pre + field;
return(queryable);
}
/// <summary>
/// 排序
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="queryable"></param>
/// <param name="orderFileds">如：id asc,name desc </param>
/// <returns></returns>
public static Queryable <T> OrderBy <T>(this Queryable <T> queryable, Expression <Func <T, object> > expression, OrderByType type = OrderByType.asc)
{
ResolveExpress re = new ResolveExpress();
var field = re.GetExpressionRightFiled(expression);
var pre = queryable.OrderBy.IsValuable() ? "," : "";
queryable.OrderBy += pre + field + " " + type.ToString().ToUpper();
return(queryable);
}