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 12: {
行 13:
行 14: private static string connectionString = ConfigurationManager.ConnectionStrings["NewDBConnectionString"].ToString();
行 15: ///<summary>
行 16: ///根据登录名查询用户
源文件: F:\test\News\NewsDAL\UserService.cs 行: 14 堆栈跟踪:
[NullReferenceException: 未将对象引用设置到对象的实例。]
NewsDAL.UserService..cctor() in F:\test\News\NewsDAL\UserService.cs:14[TypeInitializationException: “NewsDAL.UserService”的类型初始值设定项引发异常。]
NewsDAL.UserService.GetUserByLoginName(String loginName) in F:\test\News\NewsDAL\UserService.cs:53
NewsBLL.UserManager.UserLogin(String loginName, String loginPwd, User& validUser) in F:\test\News\NewsBLL\UserManager.cs:20
Web.kin.Admin.AdminLogin.btnLogin_Click(Object sender, EventArgs e) in F:\test\News\Web.kin\Admin\AdminLogin.aspx.cs:30
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +111
System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +110
System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565 上面是我在登录时报错,进不了数据库··求救是哪的问题啊?
web.cofing
数据库串连接: <add name="NewsDBConnectionString" connectionString="server=.; user=sa;pwd=apple30696;database=NewsDB.mdf"/>
<add name="NewsDBConnectionString" connectionString="Date Source=.\SQLEXPRESS;AttachDbFilename=|DateDirectory|\NewsDB.mdf;Integrated Security=True; User Instance = True" providerName="System.Data.SqlClient"/>
还有别的方法么,哪种好啊·
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 12: {
行 13:
行 14: private static string connectionString = ConfigurationManager.ConnectionStrings["NewDBConnectionString"].ToString();
行 15: ///<summary>
行 16: ///根据登录名查询用户
源文件: F:\test\News\NewsDAL\UserService.cs 行: 14 堆栈跟踪:
[NullReferenceException: 未将对象引用设置到对象的实例。]
NewsDAL.UserService..cctor() in F:\test\News\NewsDAL\UserService.cs:14[TypeInitializationException: “NewsDAL.UserService”的类型初始值设定项引发异常。]
NewsDAL.UserService.GetUserByLoginName(String loginName) in F:\test\News\NewsDAL\UserService.cs:53
NewsBLL.UserManager.UserLogin(String loginName, String loginPwd, User& validUser) in F:\test\News\NewsBLL\UserManager.cs:20
Web.kin.Admin.AdminLogin.btnLogin_Click(Object sender, EventArgs e) in F:\test\News\Web.kin\Admin\AdminLogin.aspx.cs:30
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +111
System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +110
System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565 上面是我在登录时报错,进不了数据库··求救是哪的问题啊?
web.cofing
数据库串连接: <add name="NewsDBConnectionString" connectionString="server=.; user=sa;pwd=apple30696;database=NewsDB.mdf"/>
<add name="NewsDBConnectionString" connectionString="Date Source=.\SQLEXPRESS;AttachDbFilename=|DateDirectory|\NewsDB.mdf;Integrated Security=True; User Instance = True" providerName="System.Data.SqlClient"/>
还有别的方法么,哪种好啊·
我试过这种,也不行··应该不是NUll吧
添加了还不行的话 建议你把这张页面重写。我也碰到过这情况 都对就是找不到错
未将对象设置到对象的实例都是说没有实例化,所以首先要判断是否为NULL再ToString()