文本框.文本有错误的值

我有一个列出当前项目的页面，如果您选择其中一个项目，它会加载带有参数的相同页面，并显示属于该项目的用户。由于某些原因，它有时(取决于项目)在用户名所在的文本框中显示项目名称。

    protected void Page_Load(object sender, EventArgs e)
    {
        var dbProxy = new DatabaseProxy();
        // No parameter, show project list
        if (this.Request.QueryString["ProjectID"] == null)
        {
            var user = new UserContainer();
            user.LoadUser(HttpContext.Current.User.Identity.Name);
            List<ProjectContainer> projects = dbProxy.GetProjects(user.UserID, true);
            foreach (ProjectContainer project in projects)
            {
                var linkButton = new Button {Text = project.ProjectName};
                this.ProjectsPanel.Controls.Add(linkButton);
            }
        }
        // We have a parameter, show users for project
        else
        {
            int projectId = int.Parse(this.Request.QueryString["ProjectID"]);
            this.LoadUsers(projectId);
        }
    }

LoadUsers函数:

    private void LoadUsers(int projectId)
    {
        var databaseProxy = new DatabaseProxy();
        List<UserContainer> users = databaseProxy.GetUsersByProject(projectId);
        foreach (UserContainer user in users)
        {
            var txtUsername = new TextBox();
            txtUsername.Text = user.Username; // <- Shows projectname!
            var txtUsername2 = new TextBox();
            txtUsername2.Text = user.Username; // <- Shows username!
            this.UserPanel.Controls.Add(txtUsername);
            this.UserPanel.Controls.Add(txtUsername2);
        }
    }

HTML代码:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="EditUsers.aspx.cs" Inherits="xxx.EditUsers1" MasterPageFile="PageStructure.Master" %>
<asp:Content ID="Content1" runat="server" ContentPlaceHolderID="ContentPlace">
    <asp:Panel ID="Panel1" runat="server" style="padding-left: 25px">
        <div style="margin-bottom: 50px">
            <asp:Label ID="lblHeader" runat="server" Text="Benutzer verwalten" CssClass="PageHeader"></asp:Label>
        </div>
        <asp:Panel ID="UserPanel" runat="server"></asp:Panel>
        <asp:Panel ID="ProjectsPanel" runat="server"></asp:Panel>
    </asp:Panel>
</asp:Content>

母版页只包含一个页眉和一个页脚，以及另一个页面的一些JavaScript。

输出:

https://i.stack.imgur.com/p49jh.png

user变量包含正确的值，并且在LoadUsers之后不会发生任何其他事情。我甚至可以添加一个空标签作为第一个元素，然后它将在第一个文本框中显示正确的用户名!我不知道为什么，但它看起来真的想在我添加的第一个元素中添加项目名称。

如何工作的例子:

    private void LoadUsers(int projectId)
    {
        var databaseProxy = new DatabaseProxy();
        List<UserContainer> users = databaseProxy.GetUsersByProject(projectId);
        foreach (UserContainer user in users)
        {
            var lbl = new Label();
            lbl.Text = ""; <- Stays invisible!
            var txtUsername = new TextBox();
            txtUsername.Text = user.Username; // <- Shows username!
            var txtUsername2 = new TextBox();
            txtUsername2.Text = user.Username; // <- Shows username!
            this.UserPanel.Controls.Add(lbl);
            this.UserPanel.Controls.Add(txtUsername);
            this.UserPanel.Controls.Add(txtUsername2);
        }
    }

我想我可以找到一个变通办法，比如把它分成两个不同的网页形式，但我仍然想知道为什么我得到了错误的值。

foreach (UserContainer user in users)
{
    var txtUsername = new TextBox();
    txtUsername.EnableViewState = false;
    txtUsername.Text = user.Username; // <- Shows projectname!
    var txtUsername2 = new TextBox();
    txtUsername2.EnableViewState = false;
    txtUsername2.Text = user.Username; // <- Shows username!
    this.UserPanel.Controls.Add(txtUsername);
    this.UserPanel.Controls.Add(txtUsername2);
}

foreach (UserContainer user in users)
{
    var txtUsername = new TextBox();
    txtUsername.ID = Guid.NewGuid().ToString("N");
    txtUsername.Text = user.Username; // <- Shows projectname!
    var txtUsername2 = new TextBox();
    txtUsername2.ID = Guid.NewGuid().ToString("N");
    txtUsername2.EnableViewState = false;
    txtUsername2.Text = user.Username; // <- Shows username!
    this.UserPanel.Controls.Add(txtUsername);
    this.UserPanel.Controls.Add(txtUsername2);
}