How to set default values for data bound controls for addition in VB.NET

vb.net add vb.net-2010 databound-controls
feldoh picture feldoh · Jun 18, 2012 · Viewed 7.7k times · Source

I have a vb.net 2010 form with 22 data bound controls from two tables held in a dataset which is navigated by a bindingnavigator. This successfully adds deletes and updates. However what I need is when adding a new record I need some of the fields to be pre filled out. More specifically I have points balance fields etc which could be any value but will normally be 0 on a new customer so I want to initialise them to 0 when adding new records.

I located an AddingNew event on my datasource but this is called before the new item is added and thus all my initialisation is lost.

any help on this would be appreciated. kind regards Feldoh

Answer

LarsTech picture LarsTech · Jun 18, 2012

Since you are using DataTables, you can manually set the DefaultValue property of the DataColumn:

Dim dt As New DataTable
Dim dc As New DataColumn("test", GetType(String))
dc.DefaultValue = "hello"
dt.Columns.Add(dc)
dt.Rows.Add()
Debug.WriteLine(dt.Rows(0)("test").ToString)

Result: hello

Related questions

What is a NullReferenceException, and how do I fix it?

I have some code and when it executes, it throws a NullReferenceException, saying: Object reference not set to an instance of an object. What does this mean, and what can I do to fix this error?

Read More
Converting string to byte array in C#

I'm converting something from VB into C#. Having a problem with the syntax of this statement: if ((searchResult.Properties["user"].Count > 0)) { profile.User = System.Text.Encoding.UTF8.GetString(searchResult.Properties["user"][0]); } I then see the following errors: Argument 1: cannot …

Read More
Why is Dictionary preferred over Hashtable in C#?

In most programming languages, dictionaries are preferred over hashtables. What are the reasons behind that?

Read More