Asp.net-Object引用未设置为对象的实例 [英] Asp.net-Object reference not set to an instance of an object

问题描述

任何人都可以告诉我有关错误对象引用未设置为对象实例的信息.

在我的应用程序中，将记录插入数据库时​​遇到此错误.

这是我的数据层类.
在数据层中，它在Throw块中引发错误.

Hi,

Can anyone tell me about the error Object reference not set to an instance of an object.

In my application I am getting this error while inserting records into the database.

Here is my Data layer class.
In data layer it is throwing the error in Throw block.

public int Insert(string _Type, string _Name, string _Address, string Postal_Address, string _Phone, string _Fax)
       {
           SqlConnection con = new SqlConnection(constr);
           con.Open();
           SqlCommand cmd = new SqlCommand("usp_proc", con);
           cmd.CommandType = CommandType.StoredProcedure;
           try
           {
               string Docket_ID;
               cmd.Parameters.AddWithValue("@_Type", _Type);
               cmd.Parameters.AddWithValue("@_Name", _Name);
               cmd.Parameters.AddWithValue("@_Address", _Address);
               cmd.Parameters.AddWithValue("@Postal_Address", Postal_Address);
               cmd.Parameters.AddWithValue("@_Phone",_Phone);
               cmd.Parameters.AddWithValue("@_Fax", _Fax);
            ;

               SqlParameter p = new SqlParameter("@Emp_ID", SqlDbType.Int);
               p.Direction = ParameterDirection.Output;
               cmd.Parameters.Add(p);
               Emp_ID = p.Value.ToString();
               return cmd.ExecuteNonQuery();

           }
           catch
           {
               throw;
           }
           finally
           {
               cmd.Dispose();
               con.Close();
               con.Dispose();
           }
       }

如果我的问题不清楚，请告诉我.
谢谢您，

Please Let me know if my question asking is not clear to solve.
Thank you,

推荐答案

对象引用未设置为对象的实例

当您尝试使用属性或调用对象的方法为null时，会发生此错误.更多详细信息:此处 [

Object reference not set to an instance of an object

This error happens when you try to use a property or call a method of an object that is null. More details: here[^]

A simple use of Visual studio DEBUGGER can tell you the object because of which it is happening. Just look at the stack trace and put a debugger on that line. Check the objects of that line and see if any one is null and you are trying to use that objects property. Handle the same.

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