ExecuteReader：尚未初始化Connection属性。 [英] ExecuteReader: Connection property has not been initialized.

问题描述

 DatabaseClass dqwb =  new  DatabaseClass（）; 
 dqwb.dbConnection（ （local）， 常规，  DWSS123 -PC，  dwss123）; 
 
 
 
 
  //   SqlConnection myConnection1 = new SqlConnection（Server =（local）; Database = General; Trusted_Connection = True;）;  
  //   myConnection1.Open（）;  
 
  //   SqlCommand com ;  
  string  str; 
 
 尝试 
 {
  //   com = new SqlCommand（）;  
 
 
 SqlCommand com =  new  SqlCommand （ 从dbo.CompanyYear中选择YearLabel）; 
 dqwb.openConnection（）; 
  //   com.CommandText =从dbo.CompanyYear中选择YearLabel;  
 
 SqlDataAdapter sda =  new  SqlDataAdapter（com）; 
 SqlDataReader reader = com.ExecuteReader（）; 
 DataTable dt =  new  DataTable（）; 
 DataSet ds =  new  DataSet（）; 
 ds.Tables.Add（dt）; 
} 
 
 
 
 
 
 
 
 
  public   void  dbConnection（ string  ProjectName112， string  databasenameName112， string  user12， string  pass12）
 {
  string  strProject = ProjectName112;  //  输入您的SQL服务器实例名称 
  string  strDatabase = databasenameName112;  //  输入您的数据库名称 
  string  strUserID = user12;  //  输入您的SQL Server用户名 
  string  strPassword = pass12;  //  输入您的SQL Server密码 
 
 
 
  //   string strProject = a; //输入您的SQL服务器实例名称 
  //   string strDatabase = b; //输入您的数据库名称 
  //   string strUserID = c; //输入您的SQL Server用户名 
  //   string strPassword = d; //输入您的SQL Server密码 
 
  string  strconn =   data source = + strProject +  ; database =  + strDatabase +  ; Persist Security Info = True;用户ID = + strUserID +  ; Password = + strPassword +  ;; 
 
 conn =  new  SqlConnection（strconn）; 
 
 
} 

解决方案

试试这样 -

< pre lang =text> SqlCommand com = new SqlCommand（从dbo.CompanyYear中选择YearLabel，myConnection1）;

DatabaseClass dqwb = new DatabaseClass();
            dqwb.dbConnection("(local)", "General", "DWSS123-PC", "dwss123");
         

          
           
            //SqlConnection myConnection1 = new SqlConnection("Server=(local);Database=General;Trusted_Connection=True;");
            //myConnection1.Open();
           
            //SqlCommand com;
            string str;
            
            try
            {
                //com = new SqlCommand();


                SqlCommand com = new SqlCommand("select YearLabel from dbo.CompanyYear");
                dqwb.openConnection();
                //com.CommandText = "select YearLabel from dbo.CompanyYear";

                SqlDataAdapter sda = new SqlDataAdapter(com);
                SqlDataReader reader = com.ExecuteReader();
                DataTable dt = new DataTable();
                DataSet ds = new DataSet();
                ds.Tables.Add(dt);
}








 public void dbConnection(string ProjectName112, string databasenameName112, string user12,string pass12)
        {
            string strProject = ProjectName112; //Enter your SQL server instance name
            string strDatabase = databasenameName112; //Enter your database name
            string strUserID = user12; // Enter your SQL Server User Name
            string strPassword = pass12; // Enter your SQL Server Password



            //string strProject = a; //Enter your SQL server instance name
            //string strDatabase = b; //Enter your database name
            //string strUserID = c; // Enter your SQL Server User Name
            //string strPassword = d; // Enter your SQL Server Password

            string strconn = "data source=" + strProject + ";database=" + strDatabase + ";Persist Security Info=True;User ID=" + strUserID + ";Password=" + strPassword + ";";
           
            conn = new SqlConnection(strconn);

           
        }

解决方案

Try like this-

SqlCommand com = new SqlCommand("select YearLabel from dbo.CompanyYear",myConnection1);

这篇关于ExecuteReader：尚未初始化Connection属性。的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！