Question

我的代码：

public bool Insertcustomer()
{
    try
    {
        SqlCommand cmd = new SqlCommand("Insertcustomermaster", dal.con);
        cmd.Parameters.Add("@customercode", SqlDbType.Int).Value = customercode;
        cmd.Parameters.Add("@customername", SqlDbType.NChar).Value = customername;
        cmd.Parameters.Add("@address1", SqlDbType.NChar).Value = address1;
        cmd.Parameters.Add("@address2", SqlDbType.NChar).Value = address1;
        cmd.Parameters.Add("@phoneno", SqlDbType.Int).Value = phoneno;
        cmd.Parameters.Add("@mobileno", SqlDbType.Int).Value = mobileno;
        cmd.Parameters.Add("@mailid", SqlDbType.NChar).Value = mailid;
        cmd.Parameters.Add("@website", SqlDbType.NChar).Value = website;
        cmd.Parameters.Add("@occupation", SqlDbType.NChar).Value = occupation;
        cmd.Parameters.Add("@status", SqlDbType.Bit).Value = status;


        cmd.CommandType = CommandType.StoredProcedure;
        return Convert.ToBoolean(cmd.ExecuteNonQuery());  //Error
    }
    catch (Exception ex)
    {
        throw ex;
    }
}

App配置：

我是新的c＃.net..im无法找到此错误..有人帮助..

Answer 1

您应该打开连接并关闭它。

string connectionString = "";
SqlConnection con = new SqlConnection(connectionString);
con.Open();

//do your coding 
con.Close();

Answer 2

错误消息说明错了。连接未打开，但已关闭。

确保已打开连接。使用Open() - 方法打开连接。

顺便说一句，摆脱try / catch-block。捕获异常并重新抛出异常有什么意义？

Answer 3

从您的代码中，您需要打开SqlCommand声明中指定的连接（dal.con）

你应该用

打开它

dal.con.Open()

在您执行ExecuteNonQuery之前

但请记住在（dal.con.Close()）之后关闭它。

我建议改变

return Convert.ToBoolean(cmd.ExecuteNonQuery());

到

dal.con.Open();
bool result = Convert.ToBoolean(cmd.ExecuteNonQuery());
dal.con.Close();
return result;

Answer 4

dal.con尚未设置或打开或其他任何内容。根据错误消息。

Answer 5

您可以发布有关连接字符串的更多信息吗？

在Webconfig中尝试：

<connectionStrings>
    <add name="connName" connectionString="//ConnectionString here"/>
</connectionStrings>

在班级中：

public static SqlConnection GetConnection()
{
    string conString = ConfigurationManager.ConnectionStrings["connName"].ConnectionString;
    SqlConnection con = new SqlConnection(conString);
    return con;
}

而不是这个：

SqlCommand cmd = new SqlCommand("Insertcustomermaster", dal.con);
        cmd.Parameters.Add("@customercode", SqlDbType.Int).Value = customercode;
        cmd.Parameters.Add("@customername", SqlDbType.NChar).Value = customername;
        cmd.Parameters.Add("@address1", SqlDbType.NChar).Value = address1;
        cmd.Parameters.Add("@address2", SqlDbType.NChar).Value = address1;
        cmd.Parameters.Add("@phoneno", SqlDbType.Int).Value = phoneno;
        cmd.Parameters.Add("@mobileno", SqlDbType.Int).Value = mobileno;
        cmd.Parameters.Add("@mailid", SqlDbType.NChar).Value = mailid;
        cmd.Parameters.Add("@website", SqlDbType.NChar).Value = website;
        cmd.Parameters.Add("@occupation", SqlDbType.NChar).Value = occupation;
        cmd.Parameters.Add("@status", SqlDbType.Bit).Value = status;


        cmd.CommandType = CommandType.StoredProcedure;
        return Convert.ToBoolean(cmd.ExecuteNonQuery());  //Error
    }
    catch (Exception ex)
    {
        throw ex;
    }

这样做：

//Method + Insert string (Guessing you want to create a register page)
    try
    {
        SqlCommand cmd = new SqlCommand(sql, GetConnection());
    //You don't have to point out the data type if it's just going to be filled in like that.
        cmd.Parameters.AddWithValue("@customercode", customercode);
        cmd.Parameters.AddWithValue("@customername", customername);
        cmd.Parameters.AddWithValue("@address1", address1);
        cmd.Parameters.AddWithValue("@address2", address2);
        cmd.Parameters.AddWithValue("@phoneno", phoneno);
        cmd.Parameters.AddWithValue("@mobileno", mobileno);
        cmd.Parameters.AddWithValue("@mailid", mailid);
        cmd.Parameters.AddWithValue("@website", website);
        cmd.Parameters.AddWithValue("@occupation", occupation);
        cmd.Parameters.AddWithValue("@status", status);
        cmd.ExecuteNonQuery();
    }
        catch (System.Data.SqlClient.SqlException ex)
        {
            // You can catch it with an error, or Just leave it empty
            string msg = "Error";
            msg += ex.Message;
            throw new Exception(msg);
        }
        //Close the connection (Not Necessary)
        GetConnection().Close();
    }

ExecuteNonQuery需要一个开放且可用的连接。连接的当前状态已关闭

5 个答案: