/// <summary>
/// 判断 OrderByClip 是否为null
/// </summary>
/// <param name="orderByClip"></param>
/// <returns></returns>
public static bool IsNullOrEmpty(OrderByClip orderByClip)
{
if ((null == orderByClip) || string.IsNullOrEmpty(orderByClip.ToString()))
{
return(true);
}
return(false);
}
/// <summary>
/// 比较
/// </summary>
/// <param name="orderByClip"></param>
/// <returns></returns>
public bool Equals(OrderByClip orderByClip)
{
if (null == orderByClip)
{
return(false);
}
return(this.ToString().Equals(orderByClip.ToString()));
}
/// <summary>
/// 去掉的表前缀
/// </summary>
/// <returns></returns>
public OrderByClip RemovePrefixTableName()
{
OrderByClip tempOrderByClip = new OrderByClip();
foreach (KeyValuePair <string, OrderByOperater> kv in this.orderByClip)
{
string keyName = kv.Key;
if (kv.Key.IndexOf('.') > 0)
{
keyName = keyName.Substring(keyName.IndexOf('.') + 1);
}
tempOrderByClip.orderByClip.Add(keyName, kv.Value);
}
return(tempOrderByClip);
}
}/// <summary>
///
/// </summary>
/// <param name="exprBody"></param>
/// <param name="orderBy"></param>
/// <returns></returns>
private static OrderByClip ToOrderByClipChild(System.Linq.Expressions.Expression exprBody, OrderByOperater orderBy)
{
if (exprBody is MemberExpression)
{
var e = (MemberExpression)exprBody;
OrderByClip gb = OrderByClip.None;
var filedProp = GetFieldName(e.Member);
if (orderBy == OrderByOperater.DESC)
{
gb = gb && CreateField(filedProp, e.Expression.Type).Desc;
}
else
{
gb = gb && CreateField(filedProp, e.Expression.Type).Asc;
}
return(gb);
}
if (exprBody is NewExpression)
{
var exNew = (NewExpression)exprBody;
var type = exNew.Constructor.DeclaringType;
var list = new List <string>(exNew.Arguments.Count);
OrderByClip gb = OrderByClip.None;
foreach (MemberExpression member in exNew.Arguments)
{
var filedProp = GetFieldName(member.Member);
if (orderBy == OrderByOperater.DESC)
{
gb = gb && CreateField(filedProp, member.Expression.Type).Desc;
}
else
{
gb = gb && CreateField(filedProp, member.Expression.Type).Asc;
}
}
return(gb);
}
if (exprBody is UnaryExpression)
{
var ueEx = (UnaryExpression)exprBody;
return(ToOrderByClipChild(ueEx.Operand, orderBy));
}
throw new Exception("暂时不支持的Order by lambda写法！请使用经典写法！");
}
/// <summary>
/// 创建分页查询
/// </summary>
/// <param name="fromSection"></param>
/// <param name="startIndex"></param>
/// <param name="endIndex"></param>
/// <returns></returns>
public virtual FromSection CreatePageFromSection(FromSection fromSection, int startIndex, int endIndex)
{
Check.Require(startIndex, "startIndex", Check.GreaterThanOrEqual <int>(1));
Check.Require(endIndex, "endIndex", Check.GreaterThanOrEqual <int>(1));
Check.Require(startIndex <= endIndex, "startIndex must be less than endIndex!");
Check.Require(fromSection, "fromSection", Check.NotNullOrEmpty);
int pageSize = endIndex - startIndex + 1;
if (startIndex == 1)
{
fromSection.PrefixString = string.Concat(" TOP ", pageSize.ToString());
}
else
{
if (OrderByClip.IsNullOrEmpty(fromSection.OrderByClip))
{
foreach (Field f in fromSection.Fields)
{
if (!f.PropertyName.Equals("*") && f.PropertyName.IndexOf('(') == -1)
{
fromSection.OrderBy(f.Asc);
break;
}
}
}
Check.Require(!OrderByClip.IsNullOrEmpty(fromSection.OrderByClip), "query.OrderByClip could not be null or empty!");
int count = fromSection.Count(fromSection);
List <Parameter> list = fromSection.Parameters;
if (endIndex > count)
{
int lastnumber = count - startIndex + 1;
if (startIndex > count)
{
lastnumber = count % pageSize;
}
fromSection.PrefixString = string.Concat(" TOP ", lastnumber.ToString());
fromSection.OrderBy(fromSection.OrderByClip.ReverseOrderByClip);
//
fromSection.TableName = string.Concat(" (", fromSection.SqlString, ") AS temp_table ");
fromSection.PrefixString = string.Empty;
fromSection.DistinctString = string.Empty;
fromSection.GroupBy(GroupByClip.None);
fromSection.Select(Field.All);
fromSection.OrderBy(fromSection.OrderByClip.ReverseOrderByClip);
fromSection.Where(WhereClip.All);
}
else
{
if (startIndex < count / 2)
{
fromSection.PrefixString = string.Concat(" TOP ", endIndex.ToString());
fromSection.TableName = string.Concat(" (", fromSection.SqlString, ") AS tempIntable ");
fromSection.PrefixString = string.Concat(" TOP ", pageSize.ToString());
fromSection.DistinctString = string.Empty;
fromSection.GroupBy(GroupByClip.None);
fromSection.Select(Field.All);
fromSection.OrderBy(fromSection.OrderByClip.ReverseOrderByClip);
fromSection.Where(WhereClip.All);
//
fromSection.TableName = string.Concat(" (", fromSection.SqlString, ") AS tempOuttable ");
fromSection.PrefixString = string.Empty;
fromSection.OrderBy(fromSection.OrderByClip.ReverseOrderByClip);
}
else
{
fromSection.PrefixString = string.Concat(" TOP ", (count - startIndex + 1).ToString());
fromSection.OrderBy(fromSection.OrderByClip.ReverseOrderByClip);
fromSection.TableName = string.Concat(" (", fromSection.SqlString, ") AS tempIntable ");
fromSection.PrefixString = string.Concat(" TOP ", pageSize.ToString());
fromSection.DistinctString = string.Empty;
fromSection.GroupBy(GroupByClip.None);
fromSection.Select(Field.All);
fromSection.OrderBy(fromSection.OrderByClip.ReverseOrderByClip);
fromSection.Where(WhereClip.All);
}
}
fromSection.Parameters = list;
}
return(fromSection);
}
/// <summary>
/// 两个OrderByClip相加
/// </summary>
/// <param name="leftOrderByClip"></param>
/// <param name="rightOrderByClip"></param>
/// <returns></returns>
public static OrderByClip operator &(OrderByClip leftOrderByClip, OrderByClip rightOrderByClip)
{
if (IsNullOrEmpty(leftOrderByClip) && IsNullOrEmpty(rightOrderByClip))
return None;
if (IsNullOrEmpty(leftOrderByClip))
return rightOrderByClip;
if (IsNullOrEmpty(rightOrderByClip))
return leftOrderByClip;
OrderByClip orderby = new OrderByClip();
foreach (KeyValuePair<string, OrderByOperater> kv in leftOrderByClip.orderByClip)
{
orderby.orderByClip.Add(kv.Key, kv.Value);
}
foreach (KeyValuePair<string, OrderByOperater> kv in rightOrderByClip.orderByClip)
{
if (!orderby.orderByClip.ContainsKey(kv.Key))
orderby.orderByClip.Add(kv.Key, kv.Value);
}
return orderby;
}
/// <summary>
/// 判断 OrderByClip 是否为null
/// </summary>
/// <param name="orderByClip"></param>
/// <returns></returns>
public static bool IsNullOrEmpty(OrderByClip orderByClip)
{
if ((null == orderByClip) || string.IsNullOrEmpty(orderByClip.ToString()))
return true;
return false;
}
/// <summary>
/// 比较
/// </summary>
/// <param name="orderByClip"></param>
/// <returns></returns>
public bool Equals(OrderByClip orderByClip)
{
if (null == orderByClip)
return false;
return this.ToString().Equals(orderByClip.ToString());
}
/// <summary>
/// 去掉的表前缀
/// </summary>
/// <returns></returns>
public OrderByClip RemovePrefixTableName()
{
OrderByClip tempOrderByClip = new OrderByClip();
foreach (KeyValuePair<string, OrderByOperater> kv in this.orderByClip)
{
string keyName = kv.Key;
if (kv.Key.IndexOf('.') > 0)
keyName = keyName.Substring(keyName.IndexOf('.') + 1);
tempOrderByClip.orderByClip.Add(keyName, kv.Value);
}
return tempOrderByClip;
}
