初学Gridview绑定Sqldatasource，关于Gridview.Rows.Count有点问题。

Rimoers110 2016-10-11 05:32:57

想用Gridview和Sqldatasource来实现登录操作，在用Gridview.Rows.Count判断的时候，显示出的结果让我很头疼。

第一次点击按钮是这样：

什么信息都不改，继续点第二次就好了：

帮忙支支招呗？

代码如下：

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

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">

<head runat="server">

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>

    <title></title>

</head>

<body>

    <form id="form1" runat="server">

    <div>

        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

        <br />

        <asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>

        <br />

        <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />

        <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\MDB.mdf;Integrated Security=True" ProviderName="System.Data.SqlClient" SelectCommand="SELECT [username], [password] FROM [accountinfo] WHERE (([username] = @username) AND ([password] = @password))">

            <SelectParameters>

                <asp:ControlParameter ControlID="TextBox1" Name="username" PropertyName="Text" Type="String" />

                <asp:ControlParameter ControlID="TextBox2" Name="password" PropertyName="Text" Type="String" />

            </SelectParameters>

        </asp:SqlDataSource>

        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="username" DataSourceID="SqlDataSource1">

            <Columns>

                <asp:BoundField DataField="username" HeaderText="username" ReadOnly="True" SortExpression="username" />

                <asp:BoundField DataField="password" HeaderText="password" SortExpression="password" />

            </Columns>

        </asp:GridView>

    </div>

    </form>

</body>

</html>

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.Data.SqlClient;

using System.Configuration;



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

{

    protected void Page_Load(object sender, EventArgs e)

    {}



    protected void Button1_Click(object sender, EventArgs e)

    {

        if(GridView1.Rows.Count == 1)

        {

            Response.Write("登录成功");

        }

        else

        {

            Response.Write("用户名或密码错误"); 

        }

    }

}