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C# listbox滚动条在不使用任何命令的情况下移动_C#_Asp.net - Fatal编程技术网

C# listbox滚动条在不使用任何命令的情况下移动

C# listbox滚动条在不使用任何命令的情况下移动,c#,asp.net,C#,Asp.net,我正在开发一个ASP.NET实践网站,其中包含一个列表框。当我选择一个项目时,滚动条突然移动。为什么会这样?这是常见的吗?还是我做错了什么?。。。。。。。。。我正在发布问题的截图 <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %> <!DOCTYPE html> <html xmlns="http:/

我正在开发一个ASP.NET实践网站,其中包含一个列表框。当我选择一个项目时,滚动条突然移动。为什么会这样?这是常见的吗?还是我做错了什么?。。。。。。。。。我正在发布问题的截图

    <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

    <!DOCTYPE html>

    <html xmlns="http://www.w3.org/1999/xhtml">
    <head runat="server">
        <title></title>
    </head>
    <body>
        <form id="form1" runat="server">
        <div>

            <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Refresh" />
            <br />
            <br />
            <asp:ListBox ID="ListBox1" runat="server" AutoPostBack="True" Height="120px" OnSelectedIndexChanged="ListBox1_SelectedIndexChanged" Width="202px"></asp:ListBox>
            <br />
            <br />
            <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
            <br />
            <br />
            <asp:TextBox ID="TextBox2" runat="server" OnTextChanged="TextBox2_TextChanged"></asp:TextBox>
            <br />
            <br />
            <asp:Button ID="Button2" runat="server" OnClick="Button2_Click" Text="Insert" />
            <asp:Button ID="Button3" runat="server" OnClick="Button3_Click" Text="Update" />
            <asp:Button ID="Button4" runat="server" OnClick="Button4_Click" Text="Delete" />

        </div>
        </form>
    </body>
    </html>




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

public partial class _Default : System.Web.UI.Page
{   

    SqlConnection cnn = new SqlConnection("Initial Catalog=Northwind;Data Source=localhost;Integrated Security=SSPI;");

    protected void Page_Load(object sender, EventArgs e)
    {

    }

    protected void refresh()
    {

        ListBox1.Items.Clear();

        cnn.Open();
        SqlCommand cmd = new SqlCommand("SELECT FirstName,LastName,EmployeeID FROM Employees", cnn);
        SqlDataReader dr = cmd.ExecuteReader();
        if (dr.HasRows)
        {
            while (dr.Read())
            {
                ListBox1.Items.Add(new ListItem(dr.GetString(0) + " " + dr.GetString(1),dr.GetInt32(2).ToString()));
            }
        }

        cnn.Close();

    }

    protected void Button1_Click(object sender, EventArgs e) //refresh
    {
        refresh();
    }

    protected void ListBox1_SelectedIndexChanged(object sender, EventArgs e)
    {

        cnn.Open();
        SqlCommand cmd = new SqlCommand("SELECT FirstName,LastName FROM Employees WHERE EmployeeID = @numara", cnn);
        cmd.Parameters.AddWithValue("@numara", ListBox1.SelectedValue);
        SqlDataReader dr = cmd.ExecuteReader();
        if (dr.HasRows)
        {
            while (dr.Read())
            {
                TextBox1.Text = dr.GetString(0);
                TextBox2.Text = dr.GetString(1);
            }
        }

        cnn.Close();

    }
    protected void TextBox2_TextChanged(object sender, EventArgs e)
    {

    }
    protected void Button2_Click(object sender, EventArgs e) //insert
    {
        cnn.Open();
        SqlCommand cmd = new SqlCommand("INSERT INTO Employees (FirstName, LastName) VALUES (@CalisanAdi, @CalisanSoyadi)", cnn);
        cmd.Parameters.AddWithValue("@CalisanAdi", TextBox1.Text);
        cmd.Parameters.AddWithValue("@CalisanSoyadi", TextBox2.Text);
        cmd.ExecuteNonQuery();
        cnn.Close();

        refresh();

    }

    protected void Button3_Click(object sender, EventArgs e) //update
    {
        cnn.Open();
        SqlCommand cmd = new SqlCommand("UPDATE Employees SET FirstName = @CalisanAdi , LastName = @CalisanSoyadi WHERE EmployeeID = @numara", cnn);
        cmd.Parameters.AddWithValue("@numara", ListBox1.SelectedValue);
        cmd.Parameters.AddWithValue("@CalisanAdi", TextBox1.Text);
        cmd.Parameters.AddWithValue("@CalisanSoyadi", TextBox2.Text);
        cmd.ExecuteNonQuery();
        cnn.Close();

        refresh();

    }

    protected void Button4_Click(object sender, EventArgs e) //delete
    {
        cnn.Open();
        SqlCommand cmd = new SqlCommand("DELETE FROM Employees WHERE EmployeeID = @numara", cnn);
        cmd.Parameters.AddWithValue("@numara", ListBox1.SelectedValue);
        cmd.ExecuteNonQuery();
        cnn.Close();

        refresh();

    }
}










使用制度; 使用System.Collections.Generic; 使用System.Data.SqlClient; 使用System.Linq; 使用System.Web; 使用System.Web.UI; 使用System.Web.UI.WebControl; 公共部分类\u默认值:System.Web.UI.Page { SqlConnection cnn=新SqlConnection(“初始目录=北风;数据源=本地主机;集成安全性=SSPI;”); 受保护的无效页面加载(对象发送方、事件参数e) { } 受保护的无效刷新() { ListBox1.Items.Clear(); cnn.Open(); SqlCommand cmd=newsqlcommand(“从雇员中选择FirstName、LastName、EmployeeID”,cnn); SqlDataReader dr=cmd.ExecuteReader(); 如果(哈斯罗博士) { while(dr.Read()) { ListBox1.Items.Add(新的ListItem(dr.GetString(0)+“”+dr.GetString(1)、dr.GetInt32(2.ToString()); } } cnn.Close(); } 受保护的无效按钮1\u单击(对象发送者,事件参数)//刷新 { 刷新(); } 受保护的无效列表框1\u SelectedIndexChanged(对象发送方,事件参数e) { cnn.Open(); SqlCommand cmd=newsqlcommand(“从EmployeeID=@numara的雇员中选择FirstName和LastName”,cnn); cmd.Parameters.AddWithValue(“@numara”,ListBox1.SelectedValue); SqlDataReader dr=cmd.ExecuteReader(); 如果(哈斯罗博士) { while(dr.Read()) { TextBox1.Text=dr.GetString(0); TextBox2.Text=dr.GetString(1); } } cnn.Close(); } 受保护的void TextBox2\u TextChanged(对象发送方,事件参数e) { } 受保护的无效按钮2\u单击(对象发送者,事件参数)//插入 { cnn.Open(); SqlCommand cmd=new-SqlCommand(“插入员工(FirstName,LastName)值(@CalisanAdi,@CalisanSoyadi)”,cnn; cmd.Parameters.AddWithValue(“@CalisanAdi”,TextBox1.Text); cmd.Parameters.AddWithValue(“@CalisanSoyadi”,TextBox2.Text); cmd.ExecuteNonQuery(); cnn.Close(); 刷新(); } 受保护的无效按钮3\u单击(对象发送者,事件参数)//更新 { cnn.Open(); SqlCommand cmd=new-SqlCommand(“更新员工集FirstName=@CalisanAdi,LastName=@CalisanSoyadi,其中EmployeeID=@numara”,cnn); cmd.Parameters.AddWithValue(“@numara”,ListBox1.SelectedValue); cmd.Parameters.AddWithValue(“@CalisanAdi”,TextBox1.Text); cmd.Parameters.AddWithValue(“@CalisanSoyadi”,TextBox2.Text); cmd.ExecuteNonQuery(); cnn.Close(); 刷新(); } 受保护的无效按钮4\u单击(对象发送者,事件参数)//删除 { cnn.Open(); SqlCommand cmd=newsqlcommand(“从EmployeeID=@numara的雇员中删除”,cnn); cmd.Parameters.AddWithValue(“@numara”,ListBox1.SelectedValue); cmd.ExecuteNonQuery(); cnn.Close(); 刷新(); } }
我认为这是因为当您在列表中选择一个项目时,页面被发回,这是ASP.net的预期行为。页面正在刷新,您之前选择的项目正在列表框中被选中。

请发布一些信息code@MahmoudFarahat支票,请。