[C#/ASP.NET]List<>中Sort()、Find()、FindAll()、Exist()的使用方法
[C#/ASP.NET]中List<T>真的非常好用。一个例子简单说明一下List<>中Sort()、Find()、FindAll()、Exist()的使用方法
简单介绍：
List<T>.Sort() → 排序T
List<T>.Find() → 找出一個T
List<T>.FindAll() →找出多個T
List<T>.Exist() →判斷T是否存在
示例代码：
页面文件GenericList.aspx
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<%@ Page Language=
"C#"
AutoEventWireup=
"true"
CodeFile=
"GenericList.aspx.cs"
Inherits=
"GenericList"
%>
<!DOCTYPE html PUBLIC
"-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"
>
<html xmlns=
"http://www.w3.org/1999/xhtml"
>
<head runat=
"server"
>
<title>GenericList</title>
</head>
<body>
<form id=
"form1"
runat=
"server"
>
<div>
原始資料：
<asp:GridView ID=
"GridView1"
runat=
"server"
>
</asp:GridView>
</div>
</form>
</body>
</html>
|
后台代码文件GenericList.aspx.cs
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using
System;
using
System.Collections.Generic;
using
System.Web;
using
System.Web.UI;
using
System.Web.UI.WebControls;
public
partial
class
GenericList : System.Web.UI.Page
{
protected
void
Page_Load(
object
sender, EventArgs e)
{
List<Person> lstPerson =
new
List<Person>();
lstPerson.Add(
new
Person(1,
"puma"
, 10));
lstPerson.Add(
new
Person(2,
"F6 Team"
, 20));
lstPerson.Add(
new
Person(3,
"ASP.NET"
, 30));
lstPerson.Add(
new
Person(4,
"Dotblogs"
, 40));
//原始資料顯示在GridView上
this
.GridView1.DataSource = lstPerson;
this
.GridView1.DataBind();
//List<T>.Find()
//找出Name='puma'的Person
Response.Write(
"找出Name='puma'的Person→ "
);
Response.Write(lstPerson.Find(
delegate
(Person p) {
return
p.Name ==
"puma"
; }).ToString() +
"<p>"
);
//List<T>.FindAll()
//找出Age>10的數目
Response.Write(
"找出Age>10的數目→ "
);
Response.Write(lstPerson.FindAll(
delegate
(Person p) {
return
p.Age > 10; }).Count.ToString() +
"<p>"
);
//List<T>.Exists()
//檢查Name='F6'是否存在
Response.Write(
"檢查Name='F6'是否存在→ "
);
Response.Write(lstPerson.Exists(
delegate
(Person p) {
return
p.Name ==
"F6"
; }).ToString() +
"<p>"
);
//List<T>.Sort()
//依Name升冪排序
Response.Write(
"<p>依Name升冪排序↑<br/>"
);
lstPerson.Sort(
delegate
(Person p1, Person p2) {
return
Comparer<
string
>.Default.Compare(p1.Name, p2.Name); });
foreach
(Person p
in
lstPerson)
{
Response.Write(p.ToString() +
"<br/>"
);
}
//List<T>.Sort()
//依Name降冪排序
Response.Write(
"<p>依Name降冪排序↓<br/>"
);
lstPerson.Sort(
delegate
(Person p1, Person p2) {
return
Comparer<
string
>.Default.Compare(p2.Name, p1.Name); });
foreach
(Person p
in
lstPerson)
{
Response.Write(p.ToString() +
"<br/>"
);
}
}
}
public
class
Person
{
private
int
_ID;
private
string
_Name;
private
int
_Age;
public
Person(
int
ID,
string
Name,
int
Age)
{
_ID = ID;
_Name = Name;
_Age = Age;
}
public
int
ID
{
set
{ _ID = value; }
get
{
return
_ID; }
}
public
string
Name
{
set
{ _Name = value; }
get
{
return
_Name; }
}
public
int
Age
{
set
{ _Age = value; }
get
{
return
_Age; }
}
public
override
string
ToString()
{
return
string
.Format(
"ID：{0}，Name：{1}，Age：{2}"
, _ID, _Name, _Age);
}
}
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本文地址：http://www.cnblogs.com/atree/archive/2011/02/25/Asp-Net_List_Sort_Find_FindAll_Exist.html
转自：F6 Team，http://www.dotblogs.com.tw/puma/archive/2009/05/28/asp.net-generic-list-sort-find-findall-exsit.aspx