.Net ------ 下拉框多选

如图：在下拉框中可以多选

 实现：

1、引用

<%@ Register src="../../CommonDrops/ddlMoreSelect/WebddlMoreSelect.ascx" tagname="WebddlMoreSelect" tagprefix="uc2" %>

2、使用

<uc2:WebddlMoreSelect ID="WebddlMoreSelect1" runat="server" />

3、后台赋值

    private void ddlLoad()
    {
        {//技术人员集合
            ITEM.Inherits.Bll.qdCnt4.bllFourAdminUser _bllUser = new bllFourAdminUser();
            List<ITEM.Model.qdCnt4.FourAdminUser> mList = _bllUser.GetListSelFourAdminUser3("AdminGuid,LoginID", base.EnterpriseGuid, " and RoleGuid in(select RoleGuid from tbFourAdminRole where RoleTypeFlag in(410,480))");
            Dictionary<string, string> dic = new Dictionary<string, string>();
            for (int i = 0; i <= mList.Count - 1; i++)
            {
                dic.Add(mList[i].AdminGuid, mList[i].LoginID);
            }
            this.WebddlMoreSelect1.Set_DataList_Ini(dic, 160, 200);
        }


    }

该用户控件所在位置

控件代码

<%@ Control Language="C#" AutoEventWireup="true" CodeFile="WebddlMoreSelect.ascx.cs" Inherits="CommonDrops_ddlMoreSelect_WebddlMoreSelect" %>
<%@ Register TagPrefix="cc1" Namespace="UNLV.IAP.WebControls" Assembly="DropDownCheckList" %>
<link href="styles.css" rel="stylesheet" />
<link href="../../qdAdmin/qdcss/Style02.css" rel="stylesheet" />
<asp:Literal ID="Literal1" runat="server"></asp:Literal>
<table class="ttable_border4_1"><tr><td>
<cc1:DropDownCheckList id="DropDownCheckList3" runat="server" DropImagePosition="Left" DropImageSrc="../../qdAdmin/qdimages/duoxuan_blue.png" CssClass="ttable_border_none"
                            DisplayTextCssClass="displayText3X" DisplayBoxCssStyle="checkText3" DisplayBoxCssClass="displayBox3X" CheckListCssStyle="checkText3"
                            CheckListCssClass="checklist3" TextWhenNoneChecked="可多选,请选择..." DataMember="category" DataTextField="text"
                            DataValueField="value" Separator="," ClientCodeLocation="../../CommonDrops/ddlMoreSelect/DropDownCheckList.js"
    ></cc1:DropDownCheckList></td></tr></table>

后台

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

public partial class CommonDrops_ddlMoreSelect_WebddlMoreSelect : System.Web.UI.UserControl
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {

        }
    }

    /// <summary>
    /// 控件多选数据初始化
    /// </summary>
    /// <param name="dic"></param>
    public void Set_DataList_Ini(Dictionary<string, string> dic, int iWidth, int iHeight)
    {
        string _Width = iWidth.ToString() + "px";
        string _Height = iHeight.ToString() + "px";

        StringBuilder sb = new StringBuilder();
        sb.Append("<style>");
        sb.Append(".displayBox3 { border: 1px dashed white; cursor: pointer; background-color: white;}");
        sb.Append(".displayBox3 td{ background-color: white; border-bottom-1px; border-bottom-color:red;}");
        sb.Append(".displayText3 {background-color: white; border: 1px solid #808080; padding: 4px;" + _Width + "; border-bottom-1px; border-bottom-color:red; }");
        sb.Append(".checkText3 {background-color: white; border: 1px solid #808080; padding: 4px; " + _Width + "; border-bottom-1px; border-bottom-color:red; }");
        sb.Append(".checklist3 { background-color: white; border: 1px solid #808080; padding: 4px; height: " + _Height + ";  " + _Width + "; overflow: scroll; }");
        sb.Append("</style>");
        this.Literal1.Text = sb.ToString();

        DataTable dt = new DataTable();
        dt.Columns.Add("text");
        dt.Columns.Add("value");
        foreach (string key in dic.Keys)
        {
            DataRow drow = dt.NewRow();
            drow["value"] = key;
            drow["text"] = dic[key];
            dt.Rows.Add(drow);
        }

        this.DropDownCheckList3.DataSource = dt;
        this.DropDownCheckList3.DataBind();
    }

    public void Set_Enabled(bool flag)
    {
        this.DropDownCheckList3.Enabled = false;
    }

    public string Get_CheckList_Values()
    {
        string s = string.Empty;
        for (int i = 0; i <= this.DropDownCheckList3.Items.Count - 1; i++)
        {
            if (this.DropDownCheckList3.Items[i].Selected == true)
            {
                string sign = s == string.Empty ? "" : ",";
                s += sign + this.DropDownCheckList3.Items[i].Value;
            }
        }
        return s;
    }

    public string Get_CheckList_Texts()
    {
        string s = string.Empty;
        for (int i = 0; i <= this.DropDownCheckList3.Items.Count - 1; i++)
        {
            if (this.DropDownCheckList3.Items[i].Selected == true)
            {
                string sign = s == string.Empty ? "" : ",";
                s += sign + this.DropDownCheckList3.Items[i].Text;
            }
        }
        return s;
    }

    public string _Values
    {
        get
        {
            return Get_CheckList_Values();
        }
        set
        {
            Load_DataListbyValue(value);
        }
    }

    public string _Texts
    {
        get
        {
            return Get_CheckList_Texts();
        }
        set
        {
            Load_DataListbyText(value);
        }
    }

    /// <summary>
    /// 初始数据Value值载入
    /// </summary>
    /// <param name="s"></param>
    public void Load_DataListbyValue(string s)
    {
        s = s.Replace("，", ",").Replace("|", ",").Replace("~", ",");
        s = "," + s + ",";
        s = s.Replace(",,", ",");
        for (int i = 0; i <= this.DropDownCheckList3.Items.Count - 1; i++)
        {
            string svalue = "," + this.DropDownCheckList3.Items[i].Value + ",";
            if (s.IndexOf(svalue) >= 0)
            {
                this.DropDownCheckList3.Items[i].Selected = true;
            }
        }
    }
    /// <summary>
    /// 初始数据Text值载入
    /// </summary>
    /// <param name="s"></param>
    public void Load_DataListbyText(string s)
    {
        s = s.Replace("，", ",").Replace("|", ",").Replace("~", ",");
        s = "," + s + ",";
        s = s.Replace(",,", ",");
        for (int i = 0; i <= this.DropDownCheckList3.Items.Count - 1; i++)
        {
            string svalue = "," + this.DropDownCheckList3.Items[i].Text + ",";
            if (s.IndexOf(svalue) >= 0)
            {
                this.DropDownCheckList3.Items[i].Selected = true;
            }
        }
    }
}