How do I change the BG color of a Single Cell & store the color scheme in Textfile?

Hello all,

This thread will be a 2 part question.
A) How do I change the BG color of a Single Cell on a Table?
B) How can I store the color scheme, so that the cell BG color will be the same when program is re-opened?

A)
1) User clicks a Cell on the table
Attachment 167899
2) Then clicks a button called "Color"
3) A color window pops up
Attachment 167901
4) User choose Color and clicks OK
5) Color window closes
6) The Cell BG color changes according to user's choice

Previously, I have this code that change the color of the whole row. Now I just want ONE cell.
I want to ask, how do you make the system know which Cell is selected?

Code:

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Private Sub ProjectsDataGridView_CellFormatting(sender As System.Object, e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) Handles ProjectsDataGridView.CellFormatting


        If Me.ProjectsDataGridView.Columns(e.ColumnIndex).Name = "DataGridViewTextBoxColumnJobStatus" Then
            If e.Value IsNot Nothing Then
                If Not IsDBNull(e.Value) Then
                    If CType(e.Value, String) = "Confirmed" Then
                        ProjectsDataGridView.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(0)))
                    ElseIf CType(e.Value, String) = "On Hold" Then
                        ProjectsDataGridView.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(1)))
                    ElseIf CType(e.Value, String) = "Completed" Then
                        ProjectsDataGridView.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(2)))
                    ElseIf CType(e.Value, String) = "Incomplete" Then
                        ProjectsDataGridView.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(3)))
                    ElseIf CType(e.Value, String) = "Cancelled" Then
                        ProjectsDataGridView.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(4)))
                    ElseIf CType(e.Value, String) = "Urgent" Then
                        ProjectsDataGridView.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(5)))
                     
                    End If
                End If
            End If
        End If
    End Sub

---

=================================================================

B) The BG color must be persistent, meaning it must be saved somewhere (I am considering Textfile)
The program will then read from textfile to populate the correct colors.

(I have a column with auto-generated number called ID)

TextFile
121,description=-65536
125,client=-1

This is the one that I am really unsure if it is doable. The issue is, user may add/delete/sort the table.
How will the system remember which Cell should hold the color if the table is modified.
I am considering using ID as X and Column Name as the Y, but I need advise.

To set one cell backcolor...

Code:

---

ProjectsDataGridView.Rows(e.RowIndex).Cells(e.ColumnIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(5)))

---

To save a record, I'd use a text file, with one line per affected cell, i.e....

columnIndex,rowIndex,color.ToARGB

Then on Form_Load, read the text file line by line and change BackColor for any cells that should be changed

If the table is modified, you'll need to loop through your text file and edit any affected column or row indices

Or, it might be easier, to just write your text file on Form_FormClosing, then you won't need to keep updating it when your user deletes rows or makes any other changes to the structure of the table

Quote:

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Originally Posted by .paul.

To set one cell backcolor...

Code:

---

ProjectsDataGridView.Rows(e.RowIndex).Cells(e.ColumnIndex).DefaultCellStyle.BackColor = Color.FromArgb(CInt(colorArray(5)))

---

To save a record, I'd use a text file, with one line per affected cell, i.e....

columnIndex,rowIndex,color.ToARGB

Then on Form_Load, read the text file line by line and change BackColor for any cells that should be changed

---

But what is the code to check which cell is currently selected?
Like e.SelectedCell or something?
If user selects a cell and click “color” button.

Just use the CurrentCell...

Code:

---

DataGridView1.CurrentCell.Style.BackColor = Color.Magenta

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Hi

here some ways to get the x y of the Cells, or like paul say's use CurrentCell

for the sample add the controls you see in the code

Code:

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Public Class Form4
    'https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.datagridview.invalidatecell?view=netframework-4.8
    'Force repaint when mouse enters Cell
    Private Sub Form4_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        With DataGridView1
            .ColumnCount = 5
            .RowCount = 10

            For i As Integer = 0 To .ColumnCount - 1
                .Columns(i).HeaderText = "Column " & i.ToString
            Next
            For i As Integer = 0 To .Rows.Count - 1
                For j As Integer = 0 To .ColumnCount - 1
                    .Rows(i).Cells(j).Value = "C " & i.ToString & "." & j.ToString
                Next
            Next
            DataGridView1.Rows(2).Cells(3).Style.BackColor = Color.DarkOrange
            .InvalidateCell(DataGridView1.CurrentCell)

        End With
    End Sub

    Private Sub DataGridView1_CellEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellEnter

        DataGridView1.InvalidateCell(DataGridView1.CurrentCell)
        TextBox1.Text = DataGridView1.CurrentCellAddress.ToString & ": " & DataGridView1.CurrentCell.Style.BackColor.ToArgb
    End Sub

    Private Sub DataGridView1_CellLeave(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellLeave
        DataGridView1.InvalidateCell(DataGridView1.CurrentCell)
    End Sub

   
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        'read Cell x y value
        With DataGridView1
            Dim s As String = .SelectedCells(0).RowIndex.ToString & ":" & _
                              .SelectedCells(0).ColumnIndex.ToString
            MessageBox.Show(s)
        End With
    End Sub
End Class

---

hth

Quote:

---

Originally Posted by .paul.

Or, it might be easier, to just write your text file on Form_FormClosing, then you won't need to keep updating it when your user deletes rows or makes any other changes to the structure of the table

---

Hi Paul.
Can you explain more about how to use Form_FormClosing?

If let’s say user change color at row 2 column 3.
Then user add/delete/sort
Will the Cell color shift accordingly or stay as the NEW row 2 column 3?

Opps, double post

If you change a cell color, then wherever that cell moves to the backcolor will remain the same, so if it's column 0 row 2, and you delete row 1, the cell will now be column 0, row 1.

In the FormClosing event, loop through all cells in your dgv. If the color isn't standard, add a row to your textfile

Quote:

---

Originally Posted by .paul.

If you change a cell color, then wherever that cell moves to the backcolor will remain the same, so if it's column 0 row 2, and you delete row 1, the cell will now be column 0, row 1.

In the FormClosing event, loop through all cells in your dgv. If the color isn't standard, add a row to your textfile

---

If the table is ever changing, how should I save the cell color in a text file?
User may close and reopen program.

Quote:

---

Originally Posted by Volkof

If the table is ever changing, how should I save the cell color in a text file?
User may close and reopen program.

---

As I said... Save colors on close, load colors on open.
That's why I said look at the FormClosing event for saving, and as I assumed you'd guess, the Load event for reloading. You just need nested loops to save and then loop through the text file on load, where you will have saved column index, row index, and color (integer)

Ok, I can't figure out how to save the Row, Column, and Color Code.
Can someone please take a look?

rowIndex,columnIndex,color.ToARGB

Code:

---

Private Sub color_Btn_Click(sender As Object, e As EventArgs) Handles color_Btn.Click

Dim clrDialog As New ColorDialog
        Dim ColorString As String
        Dim rowIndex As Integer
        Dim colIndex As Integer

        If clrDialog.ShowDialog = Windows.Forms.DialogResult.OK Then
            ProjectsDataGridView.CurrentCell.Style.BackColor = clrDialog.Color

            ColorString = clrDialog.Color.ToArgb.ToString              'Get Color Code
            ProjectsDataGridView.CurrentRow = rowIndex            'Get Row Index
            ProjectsDataGridView.Current??? = colIndex                'Get Col Index


        End If
        clrDialog.Dispose()

End Sub

---

Ok, I can't figure out how to save the Row, Column, and Color Code.
Can someone please take a look?

rowIndex,columnIndex,color.ToARGB

Code:

---

Private Sub color_Btn_Click(sender As Object, e As EventArgs) Handles color_Btn.Click

Dim clrDialog As New ColorDialog
        Dim ColorString As String
        Dim rowIndex As Integer
        Dim colIndex As Integer

        If clrDialog.ShowDialog = Windows.Forms.DialogResult.OK Then
            ProjectsDataGridView.CurrentCell.Style.BackColor = clrDialog.Color

            ColorString = clrDialog.Color.ToArgb.ToString              'Get Color Code
            rowIndex = ProjectsDataGridView.CurrentRow            'Get Row Index
            colIndex = ProjectsDataGridView.CurrentCol                'Get Col Index           


        End If
        clrDialog.Dispose()

End Sub

---

You have a Form which contains a DataGridView. What Form event would you expect to fire when your Form is closing??? Would it not make sense to loop through all of the rows of your DataGridView, and for each row loop through all of the cells in that row, then for each cell, check if the backcolor has changed, and if so, store that information in a text file???
And having a text file, wouldn't you wonder if there was a Form event that fires when the Form loads??? Then you could split each line in your text file and use it to restore the colors to your DataGridView...

Or you could just hang around here until someone writes every last word of it for you :D

Quote:

---

Originally Posted by .paul.

You have a Form which contains a DataGridView. What Form event would you expect to fire when your Form is closing??? Would it not make sense to loop through all of the rows of your DataGridView, and for each row loop through all of the cells in that row, then for each cell, check if the backcolor has changed, and if so, store that information in a text file???
And having a text file, wouldn't you wonder if there was a Form event that fires when the Form loads??? Then you could split each line in your text file and use it to restore the colors to your DataGridView...

Or you could just hang around here until someone writes every last word of it for you :D

---

Sir, I understand the logic.
But my VB programming skill is not very good, I don't know the exact code to write.
which is why I am struggling.

So firstly, I am trying to figure out how to loop through the DataGridView
Can I get some help?

Code:

---

Private Sub color_Btn_Click(sender As Object, e As EventArgs) Handles color_Btn.Click

        Dim clrDialog As New ColorDialog
        Dim colorString As String
        'Dim rowIndex As Integer
        'Dim colIndex As Integer

        If clrDialog.ShowDialog = Windows.Forms.DialogResult.OK Then
            ProjectsDataGridView.CurrentCell.Style.BackColor = clrDialog.Color

            colorString = clrDialog.Color.ToArgb.ToString              'Get Color Code
            'rowIndex = ProjectsDataGridView.CurrentRow                  'Get Row Index
            'colIndex = ProjectsDataGridView.CurrentCol                  'Get Col Index

        End If
        clrDialog.Dispose()

        'Loop through the DataGridView, find Cell where backcolor = changed, store rowIndex,columnIndex,color.ToARGB

        "How should I code this?"

    End Sub

---

Sorry if I'm slow...


Also, sorry for the update, but I need to save the rowIndex,columnIndex,color.ToARGB when user clicks the Color button, not when the Form Closes, cuz the same program is running on another computer, and the color will update there also. (This one I will figure it out myself, so it is ok)

Quote:

---

Originally Posted by Volkof

But my VB programming skill is not very good, I don't know the exact code to write.

---

We don't expect you to know already, but not knowing the exact code already doesn't mean you shouldn't try to work it out - based on the things you do know, the examples you have seen, and the information available (there are lots of tutorials and examples on the internet).

We are here to help you with things that are too hard to work out yourself, not to save you the effort of trying to do the things you could do... in this case you haven't even started writing a loop (which is something you shouldn't ask us for help with, thousand of tutorials cover loops, and part of post 7 above is useful), you've just asked us to write it all for you.

Being concerned that you can't do all of it doesn't mean you should avoid doing anything.

Do the bits you can, and put in some effort to find out how to do the other parts. If you get stuck then show us what you've come up with, and explain what you are stuck with.

This is what I've got.
The bold part I could not figure out, how do you check if the Cell has Backcolor?

Code:

---

Private Sub color_Btn_Click(sender As Object, e As EventArgs) Handles color_Btn.Click

        Dim clrDialog As New ColorDialog
        Dim colorString As String
        Dim rowIndex As Integer
        Dim colIndex As Integer

        If clrDialog.ShowDialog = Windows.Forms.DialogResult.OK Then
            ProjectsDataGridView.CurrentCell.Style.BackColor = clrDialog.Color

            colorString = clrDialog.Color.ToArgb.ToString              'Get Color Code

        End If
        clrDialog.Dispose()

        'Loop through the DataGridView, find Cell where backcolor = changed, store rowIndex,columnIndex,color.ToARGB

        Dim i As Integer = 0        'Counter for Rows
        Dim j As Integer = 0        'Counter for Columns

        For i = 0 To ProjectsDataGridView.RowCount - 1
            For j = 0 To ProjectsDataGridView.ColumnCount - 1
                'Check if each cell has Backcolor
                If ProjectsDataGridView.Rows(i).Cells(j).Style.BackColor = True Then
                    rowIndex = i                'Get Row Index
                    colIndex = j                'Get Col Index
                End If
            Next
        Next


    End Sub

---

Hi

well you could check if something has changed but I would just write all the Data to a Text file

here a sample

Code:

---

Private Sub Button11_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button11.Click
        SaveGrid(DataGridView1, "E:\Test\color.txt")
    End Sub
    Public Sub SaveGrid(ByVal Grid As DataGridView, ByVal FileFullName As String)
        Dim Rows(Grid.RowCount - 1) As String
        Dim Cols(Grid.ColumnCount - 1) As String
        For i As Integer = 0 To Grid.RowCount - 1
            For j As Integer = 0 To Grid.ColumnCount - 1
                Cols(j) = Grid(j, i).Style.BackColor.ToArgb
            Next
            Rows(i) = Strings.Join(Cols, ";")
        Next
        System.IO.File.WriteAllText(FileFullName, Strings.Join(Rows, vbNewLine))
    End Sub

---

my DGV as 5 rows and 5 columns
this is what my Test file looks like
the value 0 is white(Empty = no Color selected)
the other valus are Red and DarkOrange

Code:

---

-65536;0;0;0;0
0;0;0;0;0
0;0;0;-29696;0
0;0;0;-65536;0
0;0;0;0;0

---

your welcome

@ChrisE... I wouldn't bother saving the colors after each change. Simpler to save on Form FormClosing, and reload on Form Load

Quote:

---

Originally Posted by ChrisE

Hi

well you could check if something has changed but I would just write all the Data to a Text file

here a sample

Code:

---

Private Sub Button11_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button11.Click
        SaveGrid(DataGridView1, "E:\Test\color.txt")
    End Sub
    Public Sub SaveGrid(ByVal Grid As DataGridView, ByVal FileFullName As String)
        Dim Rows(Grid.RowCount - 1) As String
        Dim Cols(Grid.ColumnCount - 1) As String
        For i As Integer = 0 To Grid.RowCount - 1
            For j As Integer = 0 To Grid.ColumnCount - 1
                Cols(j) = Grid(j, i).Style.BackColor.ToArgb
            Next
            Rows(i) = Strings.Join(Cols, ";")
        Next
        System.IO.File.WriteAllText(FileFullName, Strings.Join(Rows, vbNewLine))
    End Sub

---

my DGV as 5 rows and 5 columns
this is what my Test file looks like
the value 0 is white(Empty = no Color selected)
the other valus are Red and DarkOrange

Code:

---

-65536;0;0;0;0
0;0;0;0;0
0;0;0;-29696;0
0;0;0;-65536;0
0;0;0;0;0

---

---

Hi ChrisE, the issue is that the user may ADD/DELETE/SORT the DataGridView, then the texfile won't tally anymore.


@paul, I can't use FormClosing because I have another computer running the same program and the changes need to be real-time (sort-of, I have an auto-refresh function).

So I am checking if Color is not WHITE
I am thinking of only saving the ProjectsDataGridView.row(ID).value, ColumnIndex, Color
Cuz if user ADD/DELETE/SORT, ID will stay the same.
Also I don't need to store for the entire DataGridView

Attachment 167957

So in this example, Row ID 122 has color changed

TextFile
122, 0, Red
122, 1, Red
.
.
.


Then whenever the program refresh, it will read from textfile, Loop the DataGridView and check Column 0 where Value = 122, set the Cell Color

That's the idea.
I may have to come back and ask more questions

I think you are heading in the wrong directon with wanting to save the colors to a text file

or I got it wrong.

here a sample of coloring cells baseed on another cell (status changed in a row)

Code:

---

  Dim tb As DataTable = New DataTable


    Private Sub Form7_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        tb.Columns.Add("ID")
        tb.Columns.Add("QtyOut")
        tb.Columns.Add("QtyIn")
        tb.Columns.Add("Stock")
        tb.Columns.Add("Balance")
        tb.Rows.Add("1", "20", "230", "400", "Confirmed")
        tb.Rows.Add("2", "6", "210", "300", "On Hold")
        tb.Rows.Add("3", "5", "220", "25", "Incomplete")
        tb.Rows.Add("4", "4", "126", "1233", "Urgent")
        DataGridView1.DataSource = tb
    End Sub

    Private Sub ApplyFormatting()
        For Each row As DataGridViewRow In DataGridView1.Rows
            Select Case CStr(row.Cells(4).Value) 'based on Cell  4
                Case Is = "Confirmed"
                    row.Cells(0).Style.BackColor = Color.Aquamarine
                    'or any other Cell = 0 1 2 or 3 in this case
                Case Is = "On Hold"
                    row.Cells(2).Style.BackColor = Color.Pink
                Case Is = "Incomplete"
                    row.Cells(3).Style.BackColor = Color.Bisque
                Case Is = "Urgent"
                    row.Cells(2).Style.BackColor = Color.Red
            End Select
        Next
    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        ApplyFormatting()
    End Sub

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