ConnectionString 属性尚未初始化

Question

using System;
using System.Data;
using System.Configuration;
using System.Web.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;public partial class _Default : System.Web.UI.Page
{    static string strConnect = System.Configuration.ConfigurationManager.AppSettings["checkinConnectionString"];
    protected void Page_Load(object sender, EventArgs e)
    {    }
    protected void btnLogin_Click(object sender, EventArgs e)
    {
        SqlConnection objConnection = new SqlConnection(strConnect);
        SqlCommand objCommand = new SqlCommand("", objConnection);
        objCommand.CommandText = "SELECT Username,Password FROM userinfo WHERE USERNAME = @NAME AND Password = @PASSWORD";
        objCommand.Parameters.Add("NAME", SqlDbType.VarChar);
        objCommand.Parameters.Add("PASSWORD", SqlDbType.VarChar);
        objCommand.Parameters["NAME"].Value = tbxName.Text.Trim();
        objCommand.Parameters["PASSWORD"].Value = tbxPassword.Text.Trim();
        objConnection.Open();
        SqlDataReader result = objCommand.ExecuteReader();
        if (result.Read() == true)
        {
            //objCommand.ExecuteNonQuery();
            Response.Redirect("loginsuc.aspx");
        }
        else
        {
            Response.Redirect("error.aspx");
        }
        objConnection.Close();    }
    protected void btnCancel_Click(object sender, EventArgs e)
    {
        tbxName.Text = "";
        tbxPassword.Text = "";
        labError.Visible = false;
    }
}web.config里
 <connectionStrings>
      <add name="checkinConnectionString" connectionString="Data Source=(local);Initial Catalog=checkin;User ID=sa;Asynchronous Processing=True"
        providerName="System.Data.SqlClient" />
 </connectionStrings>运行时说,ConnectionString 属性尚未初始化
指向objConnection.Open();这句
请问这个问题怎么解决.
我想要实现的是登陆验证用户名和密码的问题
有高手有另外的思路也可以说来听听?!

Answer 1

SqlConnection objConnection = new SqlConnection(strConnect);
objConnection.Open();

Answer 2

static string strConnect = System.Configuration.ConfigurationManager.ConnectionStrings["checkinConnectionString"].ToString();

Answer 3

用用户输入的用户名和密码作为查询的条件去数据库里查询数据,如果能查到就表示用户存在,写Session,跳到相应页面,如果没有记录就报错啊

Answer 4

cpp2017(慕白兄) 正解啊.强人...以后多指教

Answer 5

static string strConnect = System.Configuration.ConfigurationManager.AppSettings["checkinConnectionString"];<connectionStrings>
      <add name="checkinConnectionString" connectionString="Data Source=(local);Initial Catalog=checkin;User ID=sa;Asynchronous Processing=True"
        providerName="System.Data.SqlClient" />
 </connectionStrings>2.0用static string strConnect = System.Configuration.ConfigurationManager.ConnectionStrings["checkinConnectionString"].ToString();