在DataGrid VB.Net中搜索（筛选器）

Question

I have this program that lets the user/admin search a certain student through a DataGrid. To search a student, they need to select through a ComboBox (which has Year Level, ID Number, Last Name, and Program Name respectively) and type in a corresponding search keyword on the text box. The DataGrid will be filtered according to the selected item in the ComboBox and the keyword, and only a few records will then be shown in the datagrid.

Here is the code for the search:

If cmbSearch.SelectedItem = "Year Level" Then
            Dim records = From STUDENT In StudentDB2DataSet.STUDENT Where STUDENT.YEARLEVEL Like txtKeyword.Text & "*" Select STUDENT
            STUDENTBindingSource.DataSource = records.AsDataView
        ElseIf cmbSearch.SelectedItem = "ID Number" Then
            Dim records = From STUDENT In StudentDB2DataSet.STUDENT Where STUDENT.IDNUMBER Like txtKeyword.Text & "*" Select STUDENT
            STUDENTBindingSource.DataSource = records.AsDataView
        ElseIf cmbSearch.SelectedItem = "Last Name" Then
            Dim records = From STUDENT In StudentDB2DataSet.STUDENT Where STUDENT.LNAME Like txtKeyword.Text & "*" Select STUDENT
            STUDENTBindingSource.DataSource = records.AsDataView
        ElseIf cmbSearch.SelectedItem = "Program Code" Then
            Dim records = From STUDENT In StudentDB2DataSet.STUDENT Where STUDENT.PROGCODE Like txtKeyword.Text & "*" Select STUDENT
            STUDENTBindingSource.DataSource = records.AsDataView
        End If

Although the declarations for BindingSources and the like are correct, the DataGrid does not filter according to the condition set by the ComboBox and the value in the keyword text box. It used to work before I added other blocks of codes regarding viewing of these data in another form. When I removed the block of code I added in, it still doesn't work. Does anyone know what might be wrong? I think I need to add something but I'm actually not that fluent in VB.Net. Thanks in advance!

EDIT: This is the code I have for the frmSearch_Load event. This refreshes the DataGrid with the accurate values and records from the MS Access database file.

Dim myConString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=E:\StudentDirectory2\StudentDB2.accdb"
    con.ConnectionString = myConString
    con.Open()
    da = New OleDbDataAdapter("select * from STUDENT", con)
    ds = New DataSet
    da.Fill(ds, "STUDENT")
    DataGridView1.DataSource = ds.Tables("STUDENT")
    DataGridView1.DataSource = dt
    dtTableGrd = dt

    con.Close()

    DataGridView1.DataSource = ds.Tables("STUDENT")
    con.Close()

Here is the code to populate the datagridview:

Imports System.Data.OleDb
Imports System.Data
Imports System.Collections
Imports System.IO

Public Class frmSearch

    Dim con1 As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=E:\StudentDirectory2\StudentDB2.accdb")
    Dim con As New OleDbConnection
    Dim ds As New DataSet
    Dim ds2 As New DataSet
    Dim dt As New DataTable
    Dim da As New OleDbDataAdapter
    Dim da2 As New OleDbDataAdapter

    Dim provider As String
    Dim dataFile As String
    Dim connString As String
    Public myConnection As OleDbConnection = New OleDbConnection
    Public dr As OleDbDataReader
    Public dr2 As OleDbDataReader

 Private Sub frmSearch_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'TODO: This line of code loads data into the 'StudentDB2DataSet.STUDENT' table. You can move, or remove it, as needed.
        Me.STUDENTTableAdapter.Fill(Me.StudentDB2DataSet.STUDENT)
        'TODO: This line of code loads data into the 'StudentDB2DataSet.STUDENT' table. You can move, or remove it, as needed.
        Me.STUDENTTableAdapter.Fill(Me.StudentDB2DataSet.STUDENT)
        'TODO: This line of code loads data into the 'StudentDB2DataSet.STUDENT' table. You can move, or remove it, as needed.
        Me.STUDENTTableAdapter.Fill(Me.StudentDB2DataSet.STUDENT)
        'TODO: This line of code loads data into the 'StudentDB2DataSet.STUDENT' table. You can move, or remove it, as needed.
        Me.STUDENTTableAdapter.Fill(Me.StudentDB2DataSet.STUDENT)
        'TODO: This line of code loads data into the 'UserDBDataSet.tblUser' table. You can move, or remove it, as needed.




        Dim myConString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=E:\StudentDirectory2\StudentDB2.accdb"
        con.ConnectionString = myConString
        con.Open()
        da = New OleDbDataAdapter("select * from STUDENT", con)
        ds = New DataSet
        da.Fill(ds, "STUDENT")
        DataGridView1.DataSource = ds.Tables("STUDENT")
        DataGridView1.DataSource = dt


        con.Close()

        DataGridView1.DataSource = ds.Tables("STUDENT")
        con.Close()
        'DataGridView.ColumnCount = 6
        'DataGridView.Columns(0).Name = "IDNumber"
        'DataGridView.Columns(1).Name = "LastName"
        'DataGridView.Columns(2).Name = "FirstName"
        'DataGridView.Columns(3).Name = "MiddleInitial"
        'DataGridView.Columns(4).Name = "YearLevel"
        'DataGridView.Columns(5).Name = "Program"

        'STUDENTBindingSource1.Sort = "IDNUMBER"
        'TODO: This line of code loads data into the 'StudDirDBDataSet.tblStudent' table. You can move, or remove it, as needed.

        Me.STUDENTTableAdapter.Fill(Me.StudentDB2DataSet.STUDENT)
        DataGridView1.Refresh()

        Dim user As String

        user = frmLogin.cmbUsername.SelectedItem

        If user = "User" Then
            btnUpdate.Enabled = False
            btnDelete.Enabled = False
        End If

        'Me.STUDENTTableAdapter1.Fill(Me.StudentDB2DataSet1.STUDENT)
        'TODO: This line of code loads data into the 'StudDirDBDataSet.tblStudent' table. You can move, or remove it, as needed.
        ' Me.STUDENTTableAdapter1.Fill(Me.StudentDB2DataSet1.STUDENT)
        'TODO: This line of code loads data into the 'StudDirDBDataSet.tblStudent' table. You can move, or remove it, as needed.
        ' Me.STUDENTTableAdapter1.Fill(Me.StudentDB2DataSet1.STUDENT)
        'TODO: This line of code loads data into the 'StudDirDBDataSet.tblStudent' table. You can move, or remove it, as needed.
        '  Me.STUDENTTableAdapter1.Fill(Me.StudentDB2DataSet1.STUDENT)

End Sub

Answer 1

A bit more code would be helpful, specially if u have data bindings.. Anyway this might work:

Private dtTable As New DataTable
Private dtTableGrd As DataTable

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
DataGridView1.DataSource = dtTable
    dtTableGrd = dtTable
End Sub

Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
    dtTableGrd.DefaultView.RowFilter = "ID Number Like '%" & TextBox1.Text & "%'"
End Sub