尝试在 C# 中创建测试平均值计算器并利用引导模式窗口时出现问题

这是我的问题。 我正在使用Visual Studio 2015网络表单。 我创建了一个测试平均计算器。 所有代码都有效，但是当我将其放置在模态中时，单击模态内的计算按钮会关闭模态。 计算有效，但我需要单击模态窗口才能查看结果。 这是 aspx 代码

<%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.Master"AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication7._Default" %>
<asp:Content ID="BodyContent" ContentPlaceHolderID="MainContent" runat="server">
<button type="button" class="btn btn-primary btn-lg" data-toggle="modal" data-target="#testAvgModal">Test Average</button>
<div class="modal fade" id="testAvgModal">
                <div class="modal-dialog">
                  <div class="modal-content">
                    <div class="modal-header">
                      <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
                      <h4 class="modal-title">Test Average</h4>
                    </div>
                    <div class="modal-body">
                <div class="row">
                    <br />
                    <section class="form-horizontal">
                        <div class="form-group">
                                 <label class="col-sm-4 control-label" for="t1TextBox">Test 1:  </label>
                            <div class="col-sm-2">
                                <input class="form-control" runat="server" id="t1TextBox"  required="required"  type="text" placeholder="77"/>
                            </div>
                        </div>
                    </section>
                </div>
                <div class="row">
                    <section class="form-horizontal">
                        <div class="form-group">
                                 <label class="col-sm-4 control-label" for="t2TextBox">Test 2:  </label>
                            <div class="col-sm-2">
                                <input class="form-control" runat="server" id="t2TextBox"  required="required"  type="text" placeholder="77"/>
                            </div>
                        </div>
                    </section>
                </div>
                <div class="row">
                    <section class="form-horizontal">
                        <div class="form-group">
                                 <label class="col-sm-4 control-label" for="t3TextBox">Test 3:  </label>
                            <div class="col-sm-2">
                                <input class="form-control" runat="server" id="t3TextBox"  type="text" placeholder="77"/>
                            </div>
                        </div>
                    </section>
                </div>
                <div class="row">
                    <section class="form-horizontal">
                        <div class="form-group">
                                    <label class="col-sm-4 control-label" for="avgOutputLabel">Average Test Score:  </label>
                            <div class="col-sm-2">
                                    <label class="col-sm-4 control-label" runat="server" id="avgOutputLabel"> </label>
                            </div>
                        </div>
                    </section>
                </div>
                           <div class="row">
                                <section class="form-horizontal">
                                    <div class="form-group">
                                        <div class="col-sm-4"></div>
                                        <div class="col-sm-6">
                                            <button type="submit" class="btn btn-primary" onclick="calculateButton_Click" >Calculate Average</button>
                                            <button type="reset" class="btn btn-primary" >Clear</button>
                                            <%--<asp:Button ID="calculateButton" CssClass="btn btn-success" runat="server" OnClick="calculateButton_Click" Text="Calculate Average" />--%>
                                            <%--<asp:Button ID="clearButton" CssClass="btn btn-warning" runat="server" OnClick="clearButton_Click" Text="Clear" />--%>
                                        </div>
                                    </div>
                                </section>
                           </div>
            </div>
                    <div class="modal-footer">
                      <a href="#" data-dismiss="modal" class="btn btn-info">Close</a>
                    </div>
                  </div>
                </div>
            </div>

这是背后的代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Windows.Forms;
namespace WebApplication7
{
public partial class _Default : Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
    }
    protected void calculateButton_Click(object sender, EventArgs e)
    {
            double test1;
            double test2;
            double test3;
            double average;
            test1 = double.Parse(t1TextBox.Value);
            test2 = double.Parse(t2TextBox.Value);
            test3 = double.Parse(t3TextBox.Value);
            average = (test1 + test2 + test3) / 3.0;
            avgOutputLabel.InnerText = average.ToString("N2");
    }

}
}