local variable might be not initialized before accessing c#

Question

So i try to get around this issue. I know for a fact that this will be initialized before am calling it but c# can not know this i guess. I cannot do xUser user = new xUser; One work around i was thinking about was using an List and store the values in list and then create the xuser after the while loop but it seems very messy. And i really wanna learn how to avoid this kind of errors.

        noUSer iuser = new noUSer();
        xUser user;
        string sql = "select * from accounts where id='" +id +"'";
        SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
        SQLiteDataReader reader = command.ExecuteReader();

        while (reader.Read())
        {

            iuser.user_name = reader["login"].ToString();
            iuser.password = reader["password"].ToString();
            iuser.cookie_file = @"c:\cookies";

            user = iusers.create(iguser);


        }



        m_dbConnection.Close();
        if (tab_mode.SelectedTab.Text == "User")
        {
           dothiscall(user); //Error on "user" local variable might be not initialized before accessing

        }

Initialize it to null. However, you need to be aware that if loop doesn't execute, it will remain null. — Mehrzad Chehraz, Jul 03 '16 at 02:08
Worked! Yes am aware of that. Thank you so much make it as an answer if you want. — Zara Rebecka Elisabeth Zentio, Jul 03 '16 at 02:12
Do you have a single user or multiple users? if so, with current implementation, you will call "dothiscall" only for the last one. — Mehrzad Chehraz, Jul 03 '16 at 02:16
Possible duplicate of [Why C# local variables must be initialized?](https://stackoverflow.com/questions/4182666/why-c-sharp-local-variables-must-be-initialized) — , Nov 12 '19 at 08:15

score 4 · Accepted Answer · answered Jul 03 '16 at 02:14

4

You should initialize the variable to null, however, be aware that if the code inside while loop doesn't execute, it will remain null.

answered Jul 03 '16 at 02:14

Mehrzad Chehraz

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score 0 · Answer 2 · answered Jul 03 '16 at 02:13

Yes better way is create a list iusers and add new iuser inside while loop. and your whileloop to user you are adding iguser which can not find. It should be iuser

   xUser user = new xUser();
   string sql = "select * from accounts where id='" +id +"'";
   SQLiteCommand command = new SQLiteCommand(sql, m_dbConnection);
   SQLiteDataReader reader = command.ExecuteReader();

    while (reader.Read())
    {
        noUSer iuser = new noUSer();
        iuser.user_name = reader["login"].ToString();
        iuser.password = reader["password"].ToString();
        iuser.cookie_file = @"c:\cookies";

        user = iusers.Add(iuser);

    }

score 0 · Answer 3 · answered Jul 03 '16 at 03:07

When you do:

xUser user;

You are merely creating a pointer.meaning if u had an object of type xUser later on and wanted a pointer to it you could do for example something like :

user =(xUser)DataGridView1.Rows[0].cells[myxUserObjectInCell.index].Value;

That way making changes to user will make changes to the object in your grid. However if you're planning on creating an object of type xUser,then you need to do:

xUser user = new xUser();

The new keyword makes it initialize.

local variable might be not initialized before accessing c#

3 Answers3