Are they the same or not?

[RSX02]

Hi
I have a problem. I would like to update a field in a dataset only when it's different to the value in the form.
I saw that it passed as if it was different. I put messages boxes to see if they were different but it seems like it's the same. Does somebody understand why it does this?

MsgBox("'" & dr.Item("Job_type") & "'") = 'Nothing'
MsgBox("'" & Me.JobType.SelectedValue & "'") = 'Nothing'
MsgBox(Len(dr.Item("Job_type"))) = 7
MsgBox(Len(Me.JobType.SelectedValue)) = 7
If Me.JobType.SelectedValue <> Nothing Then
If dr.Item("Job_type") <> Me.JobType.SelectedValue Then dr.Item("Job_type") = Me.JobType.SelectedValue
Else
If dr.Item("Job_type") <> "" Then dr.Item("Job_type") = ""
End If

 

[RiverGuy]

Are you saying you think calling the update method performs an update on every single row in your DataTable, regardless of whether or not changes were made?

If so, read this.

http://msdn.microsoft.com/library/d...conupdatingdatabasewithdataadapterdataset.asp

 

[RSX02]

yeah it's kind of that.
I want to create a new revision of a job only when changes has been done.
It detects the "haschange" properties as soon as I do an assignment even if both values are equal. This, I don't understand why...
that's why I put an if statement.

 

[RiverGuy]

I still don't understand completely. Are you saying you start to edit a field, but then go back and decide not the change the original value?

 

[RSX02]

No
I load my record. And, for the testing, i'm only trying to save (because if it has no change done I don't want to save it (create a new revision) but if it has changes I want to create a new revision). So as I didn't change anything between the Load record in my form and the save record. It has not supposed to change. But it seems like it has change and I don't know why...
Hope that make sense

 

[RSX02]

I found how to resolve it:
Dim str1 As String
Dim str2 As String
str1 = Trim(dr.Item("Job_type"))
str2 = Trim(Me.JobType.SelectedValue)

If str1 <> str2 Then dr.Item("Job_type") = Me.JobType.SelectedValue

This is working.