If you are filling the combobox from database(data source), you cannot delete the item while running ,datasource property wont be allowed for that.
In this case, you have to update the datasourceused to fill the combobox after each selection and then fill the combobox items after doing a clear.
Example:
Write code to delete the selected item from the datasource then fill the combobox
Dim qdfsSelDate As New SqlCommand("select distinct exec_date from t_report_master", frmSelectCategory.conMssqlSeoserver)
Dim sdsFillCom As New DataSet
dcboSelect.Items.Clear()
Dim sdaFillCom As New SqlDataAdapter(qdfsSelDate)
sdaFillCom.Fill(sdsFillCom)
qdfsSelDate.ExecuteNonQuery()
If you fill the comboxbox using datareader without binding to datasource like use a datareader to fill all relavent items in combobox by reading from datasource, then you can delete the combobox items after each selection easily without getting any error.
Hope this will help you..:)
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