如何为绑定列表框选择多个值 [英] how to select multiple values to binded listbox

问题描述

如何为绑定列表框选择多重值

我试过这个

  foreach （DataRowView drv  in  SearchView）
 {
 LstBoxAuthors.SelectedIndex = LstBoxAuthors.Items.IndexOf（ LstBoxAuthors.Items.FindByText（drv [ 1 ]。ToString（）））; 
} 

此代码选择最后一个值！

解决方案

< blockquote>检查这个 -



如何在ListBox中选择多个项目？ [ ^ ]

您好！

查看我的解决方案。您应该能够或多或少地复制并粘贴它并根据您的需要进行调整：



标记：

 <％@    页   语言  =  C＃    AutoEventWireup   =  true    CodeBehind   =  ListBox.aspx.cs   继承  =  ASPNET .ListBox   ％&g t;  
 
 <  ！DOCTYPE     html  >  
 
 < span class =code-keyword><   html     xmlns   =  http://www.w3.org/1999/xhtml >  
 <   head     runat   = < span class =code-keyword> server >  
 <   title  >  <   / title  >  
 <   / head  >  
 <  正文 >  
 <   form     id   =  form1    runat   = 服务器 >  
 <   div  >  
 <   h4  >  DB中的作者<   / h4  >  
 <   asp：ListBox  < span class =code-attribute>   runat   =  server    ID   =   AuthorsListBox   高度  =  200px   行  =  5 >  <   / asp：ListB ox  >  
 <   / div  >  
 <   div  >  
 <   h4  > 搜索<   / h4  >  
 <  标签 > 搜索作者：<   / label  >  
 <   asp：TextBox     runat   =  server    ID   =  SearchTextBox    /  >  
 <   / div  >  
 <   div  >  
 <   asp：按钮    runat   =  server    ID   =  SearchButton  
   
                                  文字  = 搜索    OnClick   =  SearchButton_Click    /  >  
 <   asp：button     runat   =  server    ID   =  ResetSearchButton  
   
  < span class =code-attribute>                          < span class =code-attribute>      文字  = 清除    OnClick   =  ResetSearchButton_Click < span class =code-attribute>   /  >  
 <   / div  >  
 <   div  >  
 <   h4  > 搜索结果<   / h4  >  
 <   asp： DataList     runat   =  server    ID   =  AuthorsDataList >  
 <   ItemTemplate  >  
 <   label  >  
 < span class =code-pagedirective>< ;％ #Eval（  AuthorName）％>  
 <   / label  >  
 <   / ItemTemplate  >  
 <   / asp：DataList  >  
 <   / div  >  
 <   / form  >  
 <   / body  >  
 <   / html  >  

代码落后：

使用System; 
使用System.Collections.Generic; 
使用System.Data; 
使用System.Linq; 
使用System.Web; 
使用System.Web.UI; 
使用System.Web.UI.WebControls; 
 
命名空间ASPNET 
 {
公共部分类ListBox：System.Web.UI.Page 
 {
 /// <  摘要 >  
 ///本地数据源变量。 
 /// <   / summary  > ;  
 private List <  作者 >  _Authors; 
 
 /// <  摘要 >  
 ///获取或设置搜索文本框。 
 /// <   / summary  > ;  
私有字符串_SearchBoxText 
 {
 get {return SearchTextBox.Text; } 
 set {SearchTextBox.Text = value; } 
} 
 
 /// <  摘要 >  
 ///预加载数据。 
 /// <   / summary  > ;  
 /// <   param     name   =  sender  >  <   / param  >  
 /// <   param    名称  =  e >  <  < span class =code-leadattribute> / param  >  
 protected void Page_ PreInit（对象发送者，EventArgs e）
 {
 _Authors = MockAuthors.GetMockAuthorData（）; 
} 
 
 /// <  摘要 >  
 ///设置控件。 
 /// <   / summary  > ;  
 /// <   param     name   =  sender  >  <   / param  >  
 /// <   param    名称  =  e >  <  < span class =code-leadattribute> / param  >  
 protected void Page_加载（对象发送者，EventArgs e）
 {
 if（！Page.IsPostBack）
 {
 AuthorsListBox.DataSource = _Authors.Select（x => x.AuthorName）; 
 AuthorsListBox.DataBind（）; 
} 
 AuthorsListBox.SelectionMode = ListSelectionMode.Multiple; 
} 
 
 /// <  摘要 >  
 ///仅返回作者姓名的数组。 
 /// <   / summary  > ;  
 /// <  返回 >  <   / returns  >  
 private IEnumerable <   string  >  GetAuthorNames（）
 {
 if（_Authors.Any（））
 {
 return _Authors.Select（x => x。 AUTHORNAME）; 
} 
返回新字符串[] {}; 
} 
 
 /// <  摘要 >  
 ///重置新搜索的控件。 
 /// <   / summary  > ;  
 private void ResetSearch（）
 {
 AuthorsListBox.SelectedIndex = -1; 
 _SearchBoxText = string.Empty; 
 AuthorsDataList.DataSource = null; 
 AuthorsDataList.DataBind（）; 
 SearchTextBox.Focus（）; 
} 
 
 /// <  摘要 >  
 ///执行作者姓名搜索。然后选择全局列表中的每个匹配数据列表项。 
 /// <   / summary  > ;  
 /// <   param     name   =  sender  >  <   / param  >  
 /// <   param    名称  =  e >  <  < span class =code-leadattribute> / param  >  
 protected void Searc hButton_Click（object sender，EventArgs e）
 {
 //重置上次搜索中的控件。 
 AuthorsListBox.SelectedIndex = -1; 
 
 //搜索匹配搜索文本的作者
列出<  作者 >  authorsMatchingSearch = 
 _Authors 
 .Where（x => 
 x.AuthorName.ToLower（）。包含（ _SearchBoxText））
 .ToList（）; 
 AuthorsDataList.DataSource = authorsMatchingSearch; 
 AuthorsDataList.DataBind（）; 
 
 //添加逻辑以便在找不到匹配项时执行某些操作。 
 
 //从主列表中选择作者
 foreach（AuthorsListBox.Items中的ListItem项目）
 {
 if（authorsMatchingSearch 
 .Select（x = > x.AuthorName.ToLower（））
 .Contains（item.Text.ToLower（）））
 {
 item.Selected = true; 
} 
} 
} 
 
 /// <  摘要 >  
 ///重置表单。 
 /// <   / summary  > ;  
 /// <   param     name   =  sender  >  <   / param  >  
 /// <   param    名称  =  e >  <  < span class =code-leadattribute> / param  >  
 protected void重置SearchButton_Click（object sender，EventArgs e）
 {
 ResetSearch（）; 
} 
} 
 
 /// <  摘要 >  
 ///表示作者实体的数据模型。 
 /// <   / summary  > ;  
公共类作者
 {
 /// <  摘要 >  
 ///作者的姓名。 
 /// <   / summary  > ;  
公共字符串AuthorName {get;组; } 
} 
 
 /// <  摘要 >  
 ///生成模拟数据。 
 /// <   / summary  > ;  
公共静态类MockAuthors 
 {
 /// <  摘要 >  
 ///模拟作者列表。 
 /// <   / summary  > ;  
 /// <  返回 >  <   / returns  >  
公共静态列表<  作者 >  GetMockAuthorData（）
 {
返回新列表<  作者 >  
 {
 new author 
 {
 AuthorName =James Smith
}，
 new author 
 {
 AuthorName =Sally Cunnigham
}，
 new author 
 {
 AuthorName =Billy Buffinger
}，
 new author 
 {
 AuthorName =James Jones
}，
 new author 
 {
 AuthorName =James Cunningham
} 
}; 
} 
} 
} 

这是成功的：

 LstBoxAuthors.Items [LstBoxAuthors.Items.IndexOf（LstBoxAuthors.Items.FindByText（drv [ 1 ]。ToString（） ））]。Selected =  true ; 
 

谢谢

how to select multible values to binded listbox
I tried this

foreach (DataRowView drv in SearchView)
            {
  LstBoxAuthors.SelectedIndex = LstBoxAuthors.Items.IndexOf(LstBoxAuthors.Items.FindByText(drv[1].ToString()));
            }

this code select just last value!

解决方案

Check this -

How to Select multiple items in ListBox?[^]

Hi there!
Check out my solution. You should be able to more or less copy and paste it and adjust for your use:

Markup:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ListBox.aspx.cs" Inherits="ASPNET.ListBox" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
        <div>
            <h4>Authors in DB</h4>
            <asp:ListBox runat="server" ID="AuthorsListBox" Height="200px" Rows="5"></asp:ListBox>
        </div>
        <div>
            <h4>Search</h4>
            <label>Search Author:</label>
            <asp:TextBox runat="server" ID="SearchTextBox" />
        </div>
        <div>
            <asp:Button runat="server" ID="SearchButton"

                Text="Search" OnClick="SearchButton_Click" />
            <asp:button runat="server" ID="ResetSearchButton"

                Text="Clear" OnClick="ResetSearchButton_Click" />
        </div>
        <div>
            <h4>Search Results</h4>
            <asp:DataList runat="server" ID="AuthorsDataList">
                <ItemTemplate>
                    <label>
                        <%#Eval("AuthorName") %>
                    </label>
                </ItemTemplate>
            </asp:DataList>
        </div>
    </form>
</body>
</html>

Code behind:

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace ASPNET
{
    public partial class ListBox : System.Web.UI.Page
    {
        /// <summary>
        /// A local data source variable.
        /// </summary>
        private List<Author> _Authors;

        /// <summary>
        /// Gets or sets the search text box.
        /// </summary>
        private string _SearchBoxText
        {
            get { return SearchTextBox.Text; }
            set { SearchTextBox.Text = value; }
        }

        /// <summary>
        /// Pre load data.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void Page_PreInit(object sender, EventArgs e)
        {
            _Authors = MockAuthors.GetMockAuthorData();
        }

        /// <summary>
        /// Set controls.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                AuthorsListBox.DataSource = _Authors.Select(x => x.AuthorName);
                AuthorsListBox.DataBind();
            }
            AuthorsListBox.SelectionMode = ListSelectionMode.Multiple;
        }

        /// <summary>
        /// Returns only an array of the author names.
        /// </summary>
        /// <returns></returns>
        private IEnumerable<string> GetAuthorNames()
        {
            if(_Authors.Any())
            {
                return _Authors.Select(x => x.AuthorName);
            }
            return new string[] { };
        }

        /// <summary>
        /// Resets controls for new search.
        /// </summary>
        private void ResetSearch()
        {
            AuthorsListBox.SelectedIndex = -1;
            _SearchBoxText = string.Empty;
            AuthorsDataList.DataSource = null;
            AuthorsDataList.DataBind();
            SearchTextBox.Focus();
        }

        /// <summary>
        /// Performs search of author names. Then selects each matching data list item in global list.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void SearchButton_Click(object sender, EventArgs e)
        {
            // Reset the controls from the previous search.
            AuthorsListBox.SelectedIndex = -1;

            // Search authors with matching search text
            List<Author> authorsMatchingSearch =
                _Authors
                .Where(x =>
                    x.AuthorName.ToLower().Contains(_SearchBoxText))
                .ToList();
            AuthorsDataList.DataSource = authorsMatchingSearch;
            AuthorsDataList.DataBind();

            // Add logic to do something when no matches found.

            // Select the authors from main list
            foreach (ListItem item in AuthorsListBox.Items)
            {
                if (authorsMatchingSearch
                    .Select(x => x.AuthorName.ToLower())
                    .Contains(item.Text.ToLower()))
                {
                    item.Selected = true;
                }
            }
        }

        /// <summary>
        /// Resets the form.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void ResetSearchButton_Click(object sender, EventArgs e)
        {
            ResetSearch();
        }
    }

    /// <summary>
    /// A data model representing an Author entity.
    /// </summary>
    public class Author
    {
        /// <summary>
        /// The name of the Author.
        /// </summary>
        public string AuthorName { get; set; }
    }

    /// <summary>
    /// Generates mock data.
    /// </summary>
    public static class MockAuthors
    {
        /// <summary>
        /// Mocks up Authors List.
        /// </summary>
        /// <returns></returns>
        public static List<Author> GetMockAuthorData()
        {
            return new List<Author>
            {
                new Author
                {
                    AuthorName = "James Smith"
                },
                new Author
                {
                    AuthorName = "Sally Cunnigham"
                },
                new Author
                {
                    AuthorName = "Billy Buffinger"
                },
                new Author
                {
                    AuthorName = "James Jones"
                },
                new Author
                {
                    AuthorName = "James Cunningham"
                }
            };
        }
    }
}

It success with this:

LstBoxAuthors.Items[LstBoxAuthors.Items.IndexOf(LstBoxAuthors.Items.FindByText(drv[1].ToString()))].Selected = true;

Thanks

这篇关于如何为绑定列表框选择多个值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！