[vb.net] Change the row color in DataGridView based on the quantity of a cell value

I need to change the color of a row in datagridview but my code is not working for me. I always get a error that says "Column named Quantity: cannot be found. Parameter name: columnName"

Here is my code:

Private Sub DataGridView1_CellFormatting(ByVal sender As Object, ByVal e As DataGridViewCellFormattingEventArgs) Handles DataGridView1.CellFormatting
    For i As Integer = 0 To Me.DataGridView1.Rows.Count - 1
        If Me.DataGridView1.Rows(i).Cells("Quantity:").Value < 5 Then
            Me.DataGridView1.Rows(i).Cells("Quantity:").Style.ForeColor = Color.Red
        End If
    Next
End Sub

Please help me fix it. Thank you.

Using the CellFormating event and the e argument:

If CInt(e.Value) < 5 Then e.CellStyle.ForeColor = Color.Red

Just remove the : in your Quantity. Make sure that your attribute is the same with the parameter you include in the code, like this:

Private Sub DataGridView1_CellFormatting(ByVal sender As Object, ByVal e As DataGridViewCellFormattingEventArgs) Handles DataGridView1.CellFormatting
    For i As Integer = 0 To Me.DataGridView1.Rows.Count - 1
        If Me.DataGridView1.Rows(i).Cells("Quantity").Value < 5 Then
            Me.DataGridView1.Rows(i).Cells("Quantity").Style.ForeColor = Color.Red
        End If
    Next
End Sub

Try this (Note: I don't have right now Visual Studio ,so code is copy paste from my archive(I haven't test it) :

Private Sub DataGridView1_CellFormatting(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) Handles DataGridView1.CellFormatting
    Dim drv As DataRowView
    If e.RowIndex >= 0 Then
        If e.RowIndex <= ds.Tables("Products").Rows.Count - 1 Then
            drv = ds.Tables("Products").DefaultView.Item(e.RowIndex)
            Dim c As Color
            If drv.Item("Quantity").Value < 5  Then
                c = Color.LightBlue
            Else
                c = Color.Pink
            End If
            e.CellStyle.BackColor = c
        End If
    End If
End Sub

Dim dgv As DataGridView = Me.TblCalendarDataGridView

For i As Integer = 0 To dgv.Rows.Count - 1
    For ColNo As Integer = 4 To 7
        If Not dgv.Rows(i).Cells(ColNo).Value Is DBNull.Value Then

            dgv.Rows(i).Cells(ColNo).Style.BackColor =  vbcolor.blue
        End If
    Next
Next

If drv.Item("Quantity").Value < 5  Then

use this to like this

If Cint(drv.Item("Quantity").Value) < 5  Then

This might be helpful

1. Use the "RowPostPaint" event
2. The name of the column is NOT the "Header" of the column. You have to go to the properties for the DataGridView => then select the column => then look for the "Name" property

I converted this from C# ('From: http://www.dotnetpools.com/Article/ArticleDetiail/?articleId=74)

    Private Sub dgv_EmployeeTraining_RowPostPaint(sender As Object, e As System.Windows.Forms.DataGridViewRowPostPaintEventArgs) 
    Handles dgv_EmployeeTraining.RowPostPaint

    If e.RowIndex < Me.dgv_EmployeeTraining.RowCount - 1 Then
        Dim dgvRow As DataGridViewRow = Me.dgv_EmployeeTraining.Rows(e.RowIndex)

    '<== This is the header Name
        'If CInt(dgvRow.Cells("EmployeeStatus_Training_e26").Value) <> 2 Then  


    '<== But this is the name assigned to it in the properties of the control
        If CInt(dgvRow.Cells("DataGridViewTextBoxColumn15").Value.ToString) <> 2 Then   

            dgvRow.DefaultCellStyle.BackColor = Color.FromArgb(236, 236, 255)

        Else
            dgvRow.DefaultCellStyle.BackColor = Color.LightPink

        End If

    End If

End Sub