Hi

I'm working at an C# 2008 and MS ACCESS app and I encounter a few problems(I'm new to SQL and C#).

The first thing I wanna do is to select the last record from one table.
If I specify the record ID everything works fine but I don't know how to go to the last record.



I tried to use IDENT_CURRENT('table') but it didn't work.


The second problem is adding the value from a check box intro a Yes/No field AND displaying the value of the Yes/No field using a check box.
I have a login table with 4 field ID, username, password and admin(Yes/No).
If I login as admin I have the possibility to change other's people right and data like password and admin rights.

The problem is how do I convert the value returned by the check box(true or false) so that I can insert it into my table when I want to update or add new users.

Here is the code for my FIND button:

This works fine if I don't try to getthe value from the "admin" field and display it as a checkbox(checked if is admin unchecked if not).

Also, when I try to update the data displayed, including the checkbox value I receive an "Update statement error":

For your first question, you can easily get the max ID of a column by using a nested query. The inner query will get the MAX of the ID_cmd and return it to the outer query which will get the data you need.



For you second question, you don't need to convert anything. Just set a string to equal Yes/No depending on whether the CheckBox is checked/unchecked. Then insert the string value into your table. This can be done with a simple IF statement.

Example:


Now update the table with the value stored in checkboxValue. Do the reverse when you read it back from the database and set the Checkbox.

What is the entire error message you get for your third question?

Thanks Jayman and sorry for the late reply. For my first question your solution worked perfect.
Howeve, for the second one nothing happened.
After setting the value of my string to Yes or No I used the string in the insert into statement and it didn't work. Could you please be mor explicit, maybe I didnt get it right.

And the error message is OleDB Connection error in UPDATE STATEMENT.

Post your revised code and lets see how you implemented the changes.

You should be using a Try/Catch to catch the errors when inserting/updating/deleting data into your database. Perhaps then you can get more verbose error messages that might indicate what you are doing wrong.


What exactly do you mean it didn't work?
- no data in table?
- failed with error message?

Are you certain you have spelled the table and column names correctly in the Insert statement?

I'm sure I din't spell the column or the table name wrong.
The table name is login and the columns are username, password and admin.
I receive the same error message: OleDB connection error in INSERT INTO statement.

My database has 6 tables and I had no problem so far. Since this is the only table containing Yes/No field I'm assuming that the error is because of this.
I also tried inserting the checkbox value using On/Off, True/False, 1/0 and 0/-1(I've noticed that this are the values stored in ACCESS for Yes/No).
I even tried to return the value of the checkbox using chkBox.CheckState.

Ok, didn't realize Access handles it differently. You can use either True/False or 0/-1.

Make sure you remove the single quotes around the value being inserted for the Yes/No field.

Hi Jayman
Sry for the late reply. Thanks for all the help.
However, iti didn'
t work that way so I changed the field type to string and I added as validation rule "Yes" or "No".
After that I declared a string var and change its value when the checkbox was checked(Yes) or not(No).
Here is the code:

Once again, thanks for your help.

HI PLEASE HELP ME WITH THE CODES WRITTEN BELOW
I WAS TRYING TO INSERT THE RECORDS FROM TWO TEXT BOXES TO ACCESS DB.
WELL THERE WERE NO ERRO BUT I STILL C`NT SEE THE VALUES IN DATABASE



void Button6Click(object sender, EventArgs e)
{
System.Data.OleDb.OleDbDataAdapter da;




string connect="Provider=Microsoft.jet.oledb.4.0;data source=.\\db1.mdb";
toolStripProgressBar1.Value=25;
OleDbConnection con = new OleDbConnection(connect);
con.Open();
DataSet ds1;
ds1=new DataSet();
//ds1.Tables.Add("r");
toolStripProgressBar1.Value=25;

string sql="select * from red";
da= new System.Data.OleDb.OleDbDataAdapter(sql,con);

System.Data.OleDb.OleDbCommandBuilder cb;
cb = new System.Data.OleDb.OleDbCommandBuilder( da );

da.Fill(ds1,"red");

int MaxRows = 0;
int inc = 0;
MaxRows = ds1.Tables["red"].Rows.Count;



//To add a record to the Dataset, you need to create a new Row
DataRow dr=ds1.Tables["red"].NewRow();

MaxRows = MaxRows + 1;
inc = MaxRows - 1;
MessageBox.Show(textBox2.Text);

//But the Row will not have any data.
//To add data to the row, the format is this:
dr[1]=textBox2.Text.ToString();
dr[2]=textBox3.Text.ToString();

toolStripProgressBar1.Value=75;


//Finally, you issue the Add command:
ds1.Tables["red"].Rows.Add(dr);
ds1.AcceptChanges();


//The only thing you need to do is tell it which Dataset holds
//all the records, and its name:

//da.Update( ds1, "Workers" );

da.Update(ds1,"red");

toolStripProgressBar1.Value=100;
con.Close();
}
}
}

Hi.

I'm still new to C# but why don't u try using an "INSERT INTO" statement instead od DataRow()?

change your this code

if (chkAdmin.Checked)
                        checkboxValue = "Yes";
                    else
                        checkboxValue = "No";

 int i;
            if (chkAdmin.Checked == true)
            {
                i = 1;
            }
            else
            {
                i = 0;
            }

Hope it help You

Thanks for the help but I already tried that option.
Anyway I already made it work by using a string.
It's all described in one of my posts.

Glad to Solve Your Problem.