Insert Records into database

First of all serach for how to create a class instance and why we need it.

Secondly how executeNonQuery works.

Third, put a breakpoint and check each line of code.

I tried but cant works too. I also change my database.cs to:
public void Insert_ItemsRecords(string id, string itemName, string itemDesc)
{
SqlCommand cmd_ItemsList = new SqlCommand();
cmd_ItemsList.CommandText = "[VRM].[INSERT_ItemsRecords]";
cmd_ItemsList.CommandType = CommandType.StoredProcedure;
cmd_ItemsList.Parameters.Clear();
SqlParameter sqlParaID = new SqlParameter("@id", SqlDbType.VarChar, 10);
sqlParaID.Value = id;
cmd_ItemsList.Parameters.Add(sqlParaID);
SqlParameter sqlParaItemName = new SqlParameter("@itemName", SqlDbType.VarChar, 100);
sqlParaItemName.Value = itemName;
cmd_ItemsList.Parameters.Add(sqlParaItemName);
SqlParameter sqlParaItemDesc = new SqlParameter("@itemDesc", SqlDbType.VarChar, 1000);
sqlParaItemDesc.Value = itemDesc;
cmd_ItemsList.Parameters.Add(sqlParaItemDesc);
return ;
}
But the error is still the same. How do I resolve it?
Thks!

Becky,
osdb is a class. Before you can use it, you must create an instance of it using "new" keyword. For example,
YourClassName osdb = new YourClassName ();
Replace YourClassName with the name of the class. Use a proper constructor.

executeNonQuery always return number.
Insert_ItemsRecords returns bool.

Your passing null value to table column. Also, check the DataTypes of inputs..

osdb.Insert_ItemsRecords((txtID.Text == null) ? 0 : txtID.Text, (txtItemName.Text == null) ? "" : txtItemName.Text, (txtItemDesc.Text == null) ? "" : txtItemDesc.Text); 

When I click on the add new button, i am unable to insert records into the database. There is an error indicating:
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

This sentence is highlighted in red:
osdb.Insert_ItemsRecords(txtID.Text, txtItemName.Text, txtItemDesc.Text);
BindGrid(true);

How do I set the osdb to a valid instance? Thanks