代码如下,当我填TextBox好点Button后,提示错误:未将对象引用设置到对象的实例。
说明: 执行当前 Web 请求期间,出现未处理的异常。请检查堆栈跟踪信息,以了解有关该错误以及代码中导致错误的出处的详细信息。 异常详细信息: System.NullReferenceException: 未将对象引用设置到对象的实例。源错误: 行 77: SqlConnection myConn = new SqlConnection(System.Configuration.ConfigurationSettings弄了一天都没弄好,高手指点迷津。辛苦了,谢谢!!!!!!!!!!!using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.Configuration;namespace 第n次
{
public class WebForm2 : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Label Label1;
protected System.Web.UI.WebControls.Label Label2;
protected System.Web.UI.WebControls.Label Label3;
protected System.Web.UI.WebControls.Label Label4;
protected System.Web.UI.WebControls.RequiredFieldValidator
RequiredFieldValidator2;
protected System.Web.UI.WebControls.Label Label5;
protected System.Web.UI.WebControls.CompareValidator CompareValidator1;
protected System.Web.UI.WebControls.TextBox nameTextBox;
protected System.Web.UI.WebControls.TextBox PasswordTextBox;
protected System.Web.UI.WebControls.TextBox PasswordagainTextBox;
protected System.Web.UI.WebControls.TextBox addressTextBox;
protected System.Web.UI.WebControls.TextBox emailTextBox;
protected System.Web.UI.WebControls.Button Button1;
protected System.Web.UI.WebControls.Panel InputPanel;
protected System.Web.UI.WebControls.Label Label6;
protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator1;
private static string strConn = System.Configuration.ConfigurationSettings.AppSettings["ConnectionStr"]; private void Page_Load(object sender, System.EventArgs e)
{
} #region Web 窗体设计器生成的代码
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
//
InitializeComponent();
base.OnInit(e);
}
private void InitializeComponent()
{
this.Button1.Click += new System.EventHandler(this.Button1_Click);
this.Load += new System.EventHandler(this.Page_Load); }
#endregion private void Button1_Click(object sender, System.EventArgs e)
{
SaveNewUser();
}
private void SaveNewUser()
{
// 连接字符串和SQL语句
string Sql = "insert into userdata (name,Password,address,email) values" + " (@s_name,@s_Password,@s_address,@s_email)";
string ConnStr = System.Configuration.ConfigurationSettings.AppSettings["ConnectionStr_kang"]; // 创建Connection和Command对象
SqlConnection myConn = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["ConnectString"].ToString());
SqlCommand myCommand = myConn.CreateCommand();
// 初始化Command对象
myCommand.CommandText = Sql;
myCommand.CommandType = CommandType.Text;
myCommand.Parameters.Add("@s_name",SqlDbType.NVarChar, 10);
myCommand.Parameters["@s_name"].Value =nameTextBox.Text;
myCommand.Parameters.Add("@s_Password", SqlDbType.NVarChar, 10);
myCommand.Parameters["@s_Password"].Value = PasswordTextBox.Text;
myCommand.Parameters.Add("@s_email", SqlDbType.NVarChar, 50);
myCommand.Parameters["@s_email"].Value = emailTextBox.Text;
myCommand.Connection.Open();
if(1 == myCommand.ExecuteNonQuery())
{
// 新增成功,隐藏输入用户信息的面板,显示“输入成功”的面板
Response.Write("添加成功");
}
else
{
Response.Write ("添加失败");
}
}
说明: 执行当前 Web 请求期间,出现未处理的异常。请检查堆栈跟踪信息,以了解有关该错误以及代码中导致错误的出处的详细信息。 异常详细信息: System.NullReferenceException: 未将对象引用设置到对象的实例。源错误: 行 77: SqlConnection myConn = new SqlConnection(System.Configuration.ConfigurationSettings弄了一天都没弄好,高手指点迷津。辛苦了,谢谢!!!!!!!!!!!using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.Configuration;namespace 第n次
{
public class WebForm2 : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Label Label1;
protected System.Web.UI.WebControls.Label Label2;
protected System.Web.UI.WebControls.Label Label3;
protected System.Web.UI.WebControls.Label Label4;
protected System.Web.UI.WebControls.RequiredFieldValidator
RequiredFieldValidator2;
protected System.Web.UI.WebControls.Label Label5;
protected System.Web.UI.WebControls.CompareValidator CompareValidator1;
protected System.Web.UI.WebControls.TextBox nameTextBox;
protected System.Web.UI.WebControls.TextBox PasswordTextBox;
protected System.Web.UI.WebControls.TextBox PasswordagainTextBox;
protected System.Web.UI.WebControls.TextBox addressTextBox;
protected System.Web.UI.WebControls.TextBox emailTextBox;
protected System.Web.UI.WebControls.Button Button1;
protected System.Web.UI.WebControls.Panel InputPanel;
protected System.Web.UI.WebControls.Label Label6;
protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator1;
private static string strConn = System.Configuration.ConfigurationSettings.AppSettings["ConnectionStr"]; private void Page_Load(object sender, System.EventArgs e)
{
} #region Web 窗体设计器生成的代码
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
//
InitializeComponent();
base.OnInit(e);
}
private void InitializeComponent()
{
this.Button1.Click += new System.EventHandler(this.Button1_Click);
this.Load += new System.EventHandler(this.Page_Load); }
#endregion private void Button1_Click(object sender, System.EventArgs e)
{
SaveNewUser();
}
private void SaveNewUser()
{
// 连接字符串和SQL语句
string Sql = "insert into userdata (name,Password,address,email) values" + " (@s_name,@s_Password,@s_address,@s_email)";
string ConnStr = System.Configuration.ConfigurationSettings.AppSettings["ConnectionStr_kang"]; // 创建Connection和Command对象
SqlConnection myConn = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["ConnectString"].ToString());
SqlCommand myCommand = myConn.CreateCommand();
// 初始化Command对象
myCommand.CommandText = Sql;
myCommand.CommandType = CommandType.Text;
myCommand.Parameters.Add("@s_name",SqlDbType.NVarChar, 10);
myCommand.Parameters["@s_name"].Value =nameTextBox.Text;
myCommand.Parameters.Add("@s_Password", SqlDbType.NVarChar, 10);
myCommand.Parameters["@s_Password"].Value = PasswordTextBox.Text;
myCommand.Parameters.Add("@s_email", SqlDbType.NVarChar, 50);
myCommand.Parameters["@s_email"].Value = emailTextBox.Text;
myCommand.Connection.Open();
if(1 == myCommand.ExecuteNonQuery())
{
// 新增成功,隐藏输入用户信息的面板,显示“输入成功”的面板
Response.Write("添加成功");
}
else
{
Response.Write ("添加失败");
}
}
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有ConnectString嘛》???
<configuration>
<appSettings>
<add key="ConnectionSqlServer " value="Server=(local);User id=sa;Pwd=;Database=Northwind"></add>
<add key="ConnectionSqlServer1" value="Server=(local);User id=sa;Pwd=;"></add>
<add key="ConnectionSqlServer_tempdb" value="Server=(local);User id=sa;Pwd=;Database=tempdb"></add>
<add key="ConnectionSqlServer_pubs" value="Server=(local);User id=sa;Pwd=;Database=pubs"></add>
<add key="ConnectionDB2" value="DATABASE=SAMPLE;UID=username;PWD=password"></add>
<add key="ConnectionOracle" value="Data Source=Oracle8i;Integrated Security=yes"></add>
</appSettings>
<system.web> <!-- 动态调试编译
设置 compilation debug="true" 以启用 ASPX 调试。否则,将此值设置为
false 将提高此应用程序的运行时性能。
设置 compilation debug="true" 以将调试符号(.pdb 信息)
插入到编译页中。因为这将创建执行起来
较慢的大文件,所以应该只在调试时将此值设置为 true,而在所有其他时候都设置为
false。有关更多信息,请参考有关
调试 ASP.NET 文件的文档。
<appSettings>
<add key="ConnectString" value="server=.;uid=sa;pwd=你的密码;database=你的数据库"/>
</appSettings>
<system.web>
....