Parent/Child Records Question

[lorena]

I am writing a windows application that interfaces with a SQL database. I want to set up a form that uses data from a parent table (RR_Record) and a child table (RR_Level) based on a value selected by a user from a combobox.

 

The form loads key values for the parent records with no problem.

 

When the user selects one of the choices in the ComboBox, the parent record should populate a series of textboxes on the form and the related child records will be a source for a DataGridView on the form.

 

I created a Data Tier/Data Access Level. Here is the code for that:

Public Class RecordAndLevelDataTier
 'Class level variables for the DataSet and TableAdapters
 Private aDataSet As RecordAndLevelDataSet
 Private aRecordTableAdapter As RecordAndLevelDataSetTableAdapters.RiskReleaseRecordTableAdapter
 Private aLevelTableAdapter As RecordAndLevelDataSetTableAdapters.RiskReleaseLevelTableAdapter

 Public Function getRecordAndLevelData() As RecordAndLevelDataSet
   'Instantiate the DataSet and TableAdapters
   aDataSet = New RecordAndLevelDataSet
   aRecordTableAdapter = New RecordAndLevelDataSetTableAdapters.RR_RecordTableAdapter
   aLevelTableAdapter = New RecordAndLevelDataSetTableAdapters.RR_LevleTableAdapter

   'Fill both of the adapters
   aRecordTableAdapter.Fill(aDataSet.RR_Record)
   aLevelTableAdapter.Fill(aDataSet.RR_Level)
   'Return the dataset
   Return aDataSet

 End Function

End Class

 

Here is the code from the windows form:

'Form Level Variables
Dim aRiskReleaseData As New RecordAndLevelDataTier
Dim aDataSet As RecordAndLevelDataSet
Private aBindingSource As BindingSource

Private Sub RiskReleaseForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _
   Handles MyBase.Load
   aDataSet = aRiskReleaseData.getRecordAndLevelData
   aBindingSource = New BindingSource
   With aBindingSource
     .DataSource = aDataSet
     .DataMember = "RiskReleaseRecord"
     .Sort = "RiskRelNo"
   End With
   With Me.rrNoComboBox
     .DataSource = aBindingSource
     .DisplayMember = "RiskRelNo"
     .ValueMember = "RiskRelNo"
     .DataBindings.Add("text", aBindingSource, "RiskRelNo", False, DataSourceUpdateMode.Never)
     .SelectedIndex = 0
   End With
End Sub

'Here is the combobox code
Private Sub rrNoComboBox_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) _
   Handles rrNoComboBox.SelectedIndexChanged
   Dim rrNoString As String
   rrNoString = rrNoComboBox.SelectedValue.ToString

   'Dim aDataSet As New DataSet

   Dim recordDataRow As DataRow
   recordDataRow = aDataSet.RiskReleaseRecord.FindByRiskRelNo(rrNoString)


   Dim levelDataRow() As DataRow
   levelDataRow = recordDataRow.GetChildRows("RecordToLevelRelation")
End Sub

 

At this point, I get "Value of type '1-dimensional array of System.Data.DataRow' cannot be converted to 'System.Data.DataRow'"

 

I know I am missing something huge. I guess I feel this is doable, I am just confused as to how to do it.

Thanks in advance for any help

[lorena]

I wound up fixing the problem. I did a rework on much of the code. Part of my problem was this line:

Dim levelDataRow() As DataRow

 

which should have been

Dim levelDataRow() As DataRow()

 

If anyone else has encountered a similiar issue, here is my solution.

Sub Load_Existing_Record()
   Dim rrNoString As String
   Dim recordDataRow As DataRow
   Dim levelDataRow As DataRow
   Dim levelDataRows As DataRow()

   Dim i As Integer

   Me.RiskReleaseRecordTableAdapter.Fill(Me.RecordAndLevelDataSet.RiskReleaseRecord)
   Me.RiskReleaseLevelTableAdapter.Fill(Me.RecordAndLevelDataSet.RiskReleaseLevel)


   Try
     rrNoString = rrNoComboBox.SelectedValue.ToString
     recordDataRow = Me.RecordAndLevelDataSet.RiskReleaseRecord.FindByRiskRelNo(rrNoString)
     levelDataRows = recordDataRow.GetChildRows("RecordToLevelRelation")
     
     Me.rrLevelDataGridView.DataSource = levelDataRows
     
   Catch ex As Exception
     MessageBox.Show("The Error is: " & ex.Message.ToString, "ERROR")
   End Try

 End Sub