using System;
using System.Data;
using System.Drawing;
using System.ComponentModel;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using DevExpress.Data;
using DevExpress.XtraGrid;
using DevExpress.LookAndFeel;

namespace DXApplication {
    public partial class Form1 : DevExpress.XtraEditors.XtraForm {
        public Form1() {
            InitializeComponent();
            gridControl1.DataSource = TaskObject.GetData();
            gridControl1.ForceInitialize();
            gridView1.OptionsView.ShowFooter = true;
            gridView1.Columns["Memory"].Summary.Add(
                new GridColumnSummaryItem(SummaryItemType.Sum, "Memory", "{0:n} MB"));
            gridView1.CustomDrawFooterCell += GridView1_CustomDrawFooterCell;
        }
        private void GridView1_CustomDrawFooterCell(object sender, DevExpress.XtraGrid.Views.Grid.FooterCellCustomDrawEventArgs e) {
            int dx = e.Bounds.Height;
            Brush brush = e.Cache.GetSolidBrush(DXSkinColors.ForeColors.Information);
            Rectangle r = e.Bounds;
            r.Inflate(-1, -1);
            e.Cache.FillRectangle(brush, r);
            r.Inflate(-6, 0);
            e.Appearance.ForeColor = Color.White;
            e.Appearance.DrawString(e.Cache, e.Info.DisplayText, r);
            e.Handled = true;
        }
    }
    public class TaskObject {
        public string AppName { get; set; }
        [DisplayFormat(DataFormatString = "p")]
        public double CPU { get; set; }
        [DisplayFormat(DataFormatString = "n")]
        public double Memory { get; set; }
        public double Network { get; set; }
        public static List<TaskObject> GetData() {
            return new List<TaskObject> {
                new TaskObject(){ AppName = "Microsoft Teams", CPU = 0.018, Memory = 402.4, Network = 0.1 },
                new TaskObject(){ AppName = "Microsoft Visual Studio 2022", CPU = 0.046, Memory = 1309.2, Network = 0 },
                new TaskObject(){ AppName = "Visual Studio Code", CPU = 0.03, Memory = 104.2, Network = 2.1 },
                new TaskObject(){ AppName = "Microsoft Edge", CPU = 0.078, Memory = 644.7, Network = 10.2 },
            };
        }
    }
}

Imports System
Imports System.Data
Imports System.Drawing
Imports System.ComponentModel
Imports System.Collections.Generic
Imports System.ComponentModel.DataAnnotations
Imports DevExpress.Data
Imports DevExpress.XtraGrid
Imports DevExpress.LookAndFeel

Namespace DXApplication
    Partial Public Class Form1
        Inherits DevExpress.XtraEditors.XtraForm

        Public Sub New()
            InitializeComponent()
            gridControl1.DataSource = TaskObject.GetData()
            gridControl1.ForceInitialize()
            gridView1.OptionsView.ShowFooter = True
            gridView1.Columns("Memory").Summary.Add(New GridColumnSummaryItem(SummaryItemType.Sum, "Memory", "{0:n} MB"))
            AddHandler gridView1.CustomDrawFooterCell, AddressOf GridView1_CustomDrawFooterCell
        End Sub
        Private Sub GridView1_CustomDrawFooterCell(ByVal sender As Object, ByVal e As DevExpress.XtraGrid.Views.Grid.FooterCellCustomDrawEventArgs)
            Dim dx As Integer = e.Bounds.Height
            Dim brush As Brush = e.Cache.GetSolidBrush(DXSkinColors.ForeColors.Information)
            Dim r As Rectangle = e.Bounds
            r.Inflate(-1, -1)
            e.Cache.FillRectangle(brush, r)
            r.Inflate(-6, 0)
            e.Appearance.ForeColor = Color.White
            e.Appearance.DrawString(e.Cache, e.Info.DisplayText, r)
            e.Handled = True
        End Sub
    End Class
    Public Class TaskObject
        Public Property AppName() As String
        <DisplayFormat(DataFormatString := "p")>
        Public Property CPU() As Double
        <DisplayFormat(DataFormatString := "n")>
        Public Property Memory() As Double
        Public Property Network() As Double
        Public Shared Function GetData() As List(Of TaskObject)
            Return New List(Of TaskObject) From {
                New TaskObject() With {.AppName = "Microsoft Teams", .CPU = 0.018, .Memory = 402.4, .Network = 0.1},
                New TaskObject() With {.AppName = "Microsoft Visual Studio 2022", .CPU = 0.046, .Memory = 1309.2, .Network = 0},
                New TaskObject() With {.AppName = "Visual Studio Code", .CPU = 0.03, .Memory = 104.2, .Network = 2.1},
                New TaskObject() With {.AppName = "Microsoft Edge", .CPU = 0.078, .Memory = 644.7, .Network = 10.2}
            }
        End Function
    End Class
End Namespace

private void GridView1_CustomDrawFooterCell(object sender, FooterCellCustomDrawEventArgs e) {
    if (e.Column.FieldName == "Bytes")
        e.Info.DisplayText = ((int)e.Info.Value / 1024).ToString() + " MBs";
}

Private Sub GridView1_CustomDrawFooterCell(ByVal sender As Object, ByVal e As FooterCellCustomDrawEventArgs)
    If e.Column.FieldName = "Bytes" Then
        e.Info.DisplayText = (DirectCast(e.Info.Value, Integer) \ 1024).ToString() & " MBs"
    End If
End Sub