VBA – Early Late Binding

Whenever you assign an object to an object variable, VB performs a process called binding. Objects can be early bound or late bound. It’s easy to tell the difference: If you declare a variable as Object, you are late binding. Early binding allows the compiler to perform other optimizations and allocate memory before an application executes, allowing the your code to run much faster. However, Late binding may be desirable In some instances.

Examples:

'Early Binding
Sub earlybinding()
'Create variable to hold new Excel App
Dim xlApp As Excel.Application
'Assign Excel App to variable
Set xlApp = New Excel.Application

'Add Workbook to xlApp & Make xlApp Visible
xlApp.Workbooks.Add
xlApp.Visible = True


End Sub

'Late Binding
Sub latebinding()

'Create variable to hold new object
Dim xlApp As Object
'Assign Excel app to Object
Set xlApp = CreateObject("Excel.Application")

'Add Workbook to xlApp & Make xlApp Visible
xlApp.Workbooks.Add
xlApp.Visible = True
End Sub