Drop Down in VB.NET

Question

I have a small requirement and that is:

There are two combo boxes on a form and for populating the employee names and roles. I am populating the combo boxes as follows

Answer 1

You need to add a binding source and a data relationship to get this to work. Consider this walk through, it is for datagridviews but the concept is the same.

I did a quick mock up to give you an idea. Remember that "EmpTable" is the name that you assign to your datatable and "EmpColumn" is the parent column, similarly apply the same logic to the Roles table. The key change to your code is that both tables must be in the same dataset with a datarelationship.

Dim dtEmp as Datatable
Dim dtRole as Datatable

''//fill tables here

Dim ds as New Dataset()
ds.Tables.add(dtRole)
ds.Tables.add(dtEmp)

Dim dr as New DataRelation( _
 ds.Tables("EmpTable").Columns("EmpColumn"),
 ds.Tables("RoleTable").Columns("RoleColumn"))

''//create binding sources
Dim bsEmp as New BindingSource
Dim bsRole as New BindingSource
bsEmp.Datasource = ds
bsEmp.DataMember = "EmpTable"
bsRole.Datasource = bsEmp
bsRole.DataMeber = "RoleTable"

''//bind the binding sources to the appropriate comboboxes
cboEmployee.Datasource = bsEmp
cboRole.Datasource = bsRole

Good luck.