在一组对象中搜索（List）

本文介绍了在一组对象中搜索（List）的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我想搜索一个对象列表，但是，代码编辑器不允许我在.aspx文件中的代码中使用此列表。 是否有其他方式搜索包含其成员静态列表作为集合一部分的对象层次结构？

BooksAndMediaOnLoan .cs ---------------------- public static List< BooksAndMediaOnLoan> BooksAndMediaOnLoanToCustomers = new List< BooksAndMediaOnLoan>（）; customermanagementpage.aspx --------------------------- protected void Button1_Click（object sender，EventArgs e） { //在媒体，图书和客户中搜索 }

参考文献： 1. www.dotnetperls/list-find - 在C＃列表中使用find方法

解决方案

代码 .cs Page和 aspx 页面是不同的页面。这意味着 customermanagementpage.aspx 页面的代码文件不是 BooksAndMediaOnLoan.cs 。 这就是为什么你不能访问其他页面上 BooksAndMediaOnLoan.cs 页面中声明的List，除了它自己的 aspx page。

如果您的BooksAndMediaOnLoan类位于customermanagementpage类的同一名称空间中 可以在BooksAndMediaOnLoanToCustomers列表中引用

BooksAndMediaOnLoan.BooksAndMediaOnLoanToCustomers

如果它位于不同的命名空间（例如bmnamespace）

bmnamespace.BooksAndMediaOnLoan.BooksAndMediaOnLoanToCustomers

这里有一个例子（两个类都在同一个命名空间）： BooksAndMediaOnLoan.cs

u唱歌系统; 使用 System.Collections.Generic; 使用 System.Linq; 使用 System.Text; 命名空间 mynamespace { class BooksAndMediaOnLoan { public static 列表< booksandmediaonloan> BooksAndMediaOnLoanToCustomers = new List< booksandmediaonloan>（）; private int _id; public int bookid { set {_ id = value ; } get { return _id; } } }

customermanagementpage.aspx.cs

使用系统; 使用 System.Collections.Generic; 使用 System.Linq; 使用 System.Web; 使用 System.Web.UI; 使用 System.Web.UI.WebControls; 使用 System.Web.Configuration; 命名空间 mynamespace { public partial class customermanagementpage：System.Web.UI.Page { 受保护 void Button1_Click（对象发​​件人，EventArgs e） { // 在媒体，书籍中搜索和客户 BooksAndMediaOnLoan book = BooksAndMediaOnLoan.BooksAndMediaOnLoanToCustomers.Find（item = > item.bookid = 100 ）; } } }

此致

I would like to search through a list of objects, however, the code editor does not allow me to use this list from the code within an .aspx file. Is there an alternative manner of searching through a hierarchy of objects that contain static lists of their members as part of a collection?

BooksAndMediaOnLoan.cs ---------------------- public static List<BooksAndMediaOnLoan> BooksAndMediaOnLoanToCustomers = new List<BooksAndMediaOnLoan>(); customermanagementpage.aspx --------------------------- protected void Button1_Click(object sender, EventArgs e) { //search within Media, Books and Customers }

References: 1. www.dotnetperls/list-find - Use find method on list within C#

解决方案

The Code .cs Page and aspx page are different pages. That means Code File for customermanagementpage.aspx page is not BooksAndMediaOnLoan.cs. That is why you can't access the List declared in BooksAndMediaOnLoan.cs page on other pages except its own aspx page.

Hi, if your BooksAndMediaOnLoan class is in the same namespace of the customermanagementpage class is it possible to refer at BooksAndMediaOnLoanToCustomers list by writing

BooksAndMediaOnLoan.BooksAndMediaOnLoanToCustomers

If it is in a different namespace (e.g. bmnamespace)

bmnamespace.BooksAndMediaOnLoan.BooksAndMediaOnLoanToCustomers

Here an example (where both classes are in the same namespace): BooksAndMediaOnLoan.cs

using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace mynamespace { class BooksAndMediaOnLoan { public static List<booksandmediaonloan> BooksAndMediaOnLoanToCustomers = new List<booksandmediaonloan>(); private int _id; public int bookid { set { _id = value; } get { return _id; } } }

customermanagementpage.aspx.cs

using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.Configuration; namespace mynamespace { public partial class customermanagementpage : System.Web.UI.Page { protected void Button1_Click(object sender, EventArgs e) { //search within Media, Books and Customers BooksAndMediaOnLoan book = BooksAndMediaOnLoan.BooksAndMediaOnLoanToCustomers.Find(item => item.bookid = 100); } } }

Regards