ObjectDataSourc用法之三(排序)

SortParameterName參數主要用於對數據源控件進尾排序

1.       准備條件

參數：ObjectDataSource用法之一(SelectMethod來進行簡單的邦定)

添加一個處理對象排序的類Reverser

public class Reverser<T> : IComparer<T>

{

private Type type = null;

private ReverserInfo info;

public Reverser(string className, string name, ReverserInfo.Direction direction)

{

try

{

this.type = Type.GetType(className, true);

this.info.name = name;

this.info.direction = direction;

}

catch (Exception e)

{

throw new Exception(e.Message);

}

}

int IComparer<T>.Compare(T t1, T t2)

{

object x = this.type.InvokeMember(this.info.name, BindingFlags.Public | BindingFlags.Instance | BindingFlags.GetProperty, null, t1, null);

object y = this.type.InvokeMember(this.info.name, BindingFlags.Public | BindingFlags.Instance | BindingFlags.GetProperty, null, t2, null);

if (this.info.direction != ReverserInfo.Direction.ASC)

Swap(ref x, ref y);

return (new CaseInsensitiveComparer()).Compare(x, y);

}

private void Swap(ref object x, ref object y)

{

object temp = null;

temp = x;

x = y;

y = temp;

}

}

public struct ReverserInfo

{

public enum Direction

{

ASC = 0,

DESC,

};

public enum Target

{

CUSTOMER = 0,

FORM,

FIELD,

SERVER,

};

public string name;

public Direction direction;

public Target target;

}

2.       在業務處理類中添加如下方法

public List<EntityMember> OrderItems(string order)

{

string orderName = order.Split(' ')[0];

ReverserInfo.Direction dir = ReverserInfo.Direction.ASC;

if (order.Split(' ').Length>1 &&　order.Split(' ')[1] == "DESC") dir = ReverserInfo.Direction.DESC;

List<EntityMember> result = new List<EntityMember>();

XmlDocument doc = new XmlDocument();

doc.Load(_path);

XmlNodeList nodes = doc.SelectNodes("/Members/Member");

foreach (XmlNode node in nodes)

{

result.Add(new EntityMember(node.SelectSingleNode("./UID").InnerText, node.SelectSingleNode("./PWD").InnerText, node.SelectSingleNode("./Email").InnerText));

}

Reverser<EntityMember> reverser = new Reverser<EntityMember>("EntityMember", orderName, dir);

result.Sort(reverser);

return result;

說明：當按降序排列的時候，參數order的內容為:屬性名稱+空格+DESC

當按升序排列的時候，參數order的內容為:屬性名稱

3.       Aspx頁面的內容為

<asp:ObjectDataSource ID="ObjectDataSource1" runat="server"

SelectMethod="OrderItems" SortParameterName="order" TypeName="Member"></asp:ObjectDataSource>

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"

DataSourceID="ObjectDataSource1" AllowSorting="true">

<Columns>

<asp:BoundField DataField="UID" HeaderText="UID" SortExpression="UID" />

<asp:BoundField DataField="PWD" HeaderText="PWD" SortExpression="PWD" />

<asp:BoundField DataField="Email" HeaderText="Email" SortExpression="Email" />

</Columns>

</asp:GridView>

說明：SortParameterName為指定SelectMethod參數指定的方法中用於排序的參數名稱