Parametized Query--Filtering a Datagrid with combo box

Question

Hi everyone

I'm still learning Csharp. And its langauge that I prefer to use to develop programs. I'm building a program that utilizes a datagrid control and a combobox. I use the combobox to filter the datagrid based on the region/city. I got this vb code, and its a bit old. And I want to re-write the code with csharp 2008. The coding style has really changed, no more things like 'generate dataset', and there are new things like 'bindingsource' . I have put the code extract that I'm more concerned with, from the attached file:

Private Sub cboCountry_SelectedIndexChanged( _
ByVal sender As System.Object, _
ByVal e As System.EventArgs) _
Handles cboCountry.SelectedIndexChanged

' Get the Parameter object and Set value
With SqlDataAdapter1.SelectCommand.Parameters
.Item("@CountryParam").Value = _
cboCountry.SelectedValue
End With

' Clear the dataset
DsCustomers1.Clear()
' Load the dataset using the parameter value
SqlDataAdapter1.Fill(DsCustomers1, "Customers")
End Sub

How do I do this? I've tried I get errors like 'missing directive'
Or do I have to re-write the entire project? How? I've put up the project, and its working except the combobox filtering part

Oageng Escobar Baruti · Answer

First let me thank everyone for participating. I figured this out. I once researched about a "How to do a dynamic search", using a TextBox and a DataGrid. And I came a across some information, the code sample was written in old VB.NET. I worked it out to the current Csharp then. Here is what my result was: private void textBox1_TextChanged(object sender, EventArgs e) { string search; search = textBox1.Text; if (search != "") customersBindingSource.Filter = "City LIKE'" + search + "%'"; else customersBindingSource.Filter = "City '123'"; } Now, out of this I worked out the solution for the ComboBox: private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { string bds_filter = comboBox1.Text; customersBindingSource.Filter = "City ='" + bds_filter + "'"; } Wonderful ! Remember the list (collection) for the ComboBox is done manually, NOT binding the ComboBox to the datasource Even this also works: private void comboBox2_SelectedIndexChanged(object sender, EventArgs e) { customersBindingSource.Filter = "City ='" + comboBox2.Text + "'"; }

Oageng Escobar Baruti · Answer

I think I've found an alternative, or the new way of doing this. But I'm failing to do the last part. For testing purposes, I've put up a DataGridView and a ComboBox, using drag and droping. Put up a DataSet, BindingSource, and TableAdadpter. Then I manually built a collection (the list of items) for the ComboBox. I did it manually to avoid duplicates of values if I was to pull it from a database table column. I also wrote the parameterized query using the xsd Query Builder: SELECT Company Name, Contact Name, Contact Title, City, Address, Region, Postal Code, Country, Phone, Fax FROM Customers WHERE City = @CityParam Then the following part requests a parameter value to fill the DataAdapter successfully, and this is where I'm stuck: private void Form1_Load(object sender, EventArgs e) { this.customersTableAdapter.Fill(this.northwindDS.Customers, string parameter ); } I have another piece of code which might be required, also that may need correction: private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { this.customersBindingSource.Filter = "City='comboBox1.SelectedValue'"; } What I really need is to use the value from the ComboBox to filter the DataGridView, or display data based on a value from the ComboBox.

Parametized Query--Filtering a Datagrid with combo box

Answers (2)