Merge multiple Images into one using C# and VB.Net in ASP.Net

Hi Apeksha,

Refer below code.

Namespaces

C#

using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Drawing.Text;
using System.IO;

VB.Net

Imports System.Collections.Generic
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Drawing.Imaging
Imports System.Drawing.Text
Imports System.IO

Code

C#

protected void MergeThreeImages(object sender, EventArgs e)
{
    Image img1 = Image.FromFile(Server.MapPath("~/QRCode/" + QRCodejJPG), true);
    Image img2 = Image.FromFile(Server.MapPath("~/StringImage/" + StringJPG), true);
    Image img3 = Image.FromFile(Server.MapPath("~/QRCodeFormet/NEWImage.png"), true);

    List<Image> fileList = new List<Image>();
    fileList.Add(img1);
    fileList.Add(img2);
    fileList.Add(img3);
    Bitmap bitmap1 = MergeImages(fileList);
    bitmap1.Save(Server.MapPath("~/FinalQRCode/") + StringJPG, ImageFormat.Jpeg);
}

public static Bitmap MergeImages(List<Image> images)
{
    int outputImageWidth = 0;
    int outputImageHeight = 1;
    foreach (Image image in images)
    {
        outputImageHeight += image.Height;
        if (image.Width > outputImageWidth)
        {
            outputImageWidth = image.Width;
        }
    }

    Bitmap outputImage = new Bitmap(outputImageWidth, outputImageHeight, System.Drawing.Imaging.PixelFormat.Format32bppArgb);

    using (Graphics graphics = Graphics.FromImage(outputImage))
    {
        graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;
        graphics.Clear(Color.White);
        graphics.DrawImage(images[0], new Rectangle(new Point(), images[0].Size), new Rectangle(new Point(), images[0].Size), GraphicsUnit.Pixel);
        graphics.DrawImage(images[1], new Rectangle(new Point(0, images[0].Height + 1), images[1].Size), new Rectangle(new Point(), images[1].Size), GraphicsUnit.Pixel);
        graphics.DrawImage(images[2], new Rectangle(new Point(0, images[0].Height + images[1].Height + 1), images[2].Size), new Rectangle(new Point(), images[2].Size), GraphicsUnit.Pixel);
    }

    return outputImage;
}

VB.Net

Protected Sub MergeThreeImages(ByVal sender As Object, ByVal e As EventArgs)
    Dim img1 As Image = Image.FromFile(Server.MapPath("~/QRCode/" & QRCodejJPG), True)
    Dim img2 As Image = Image.FromFile(Server.MapPath("~/StringImage/" & StringJPG), True)
    Dim img3 As Image = Image.FromFile(Server.MapPath("~/QRCodeFormet/NEWImage.png"), True)
    Dim fileList As List(Of Image) = New List(Of Image)()
    fileList.Add(img1)
    fileList.Add(img2)
    fileList.Add(img3)
    Dim bitmap1 As Bitmap = MergeImages(fileList)
    bitmap1.Save(Server.MapPath("~/FinalQRCode/") + StringJPG, ImageFormat.Jpeg)
End Sub

Public Shared Function MergeImages(ByVal images As List(Of Image)) As Bitmap
    Dim outputImageWidth As Integer = 0
    Dim outputImageHeight As Integer = 1

    For Each image As Image In images
        outputImageHeight += image.Height

        If image.Width > outputImageWidth Then
            outputImageWidth = image.Width
        End If
    Next

    Dim outputImage As Bitmap = New Bitmap(outputImageWidth, outputImageHeight, System.Drawing.Imaging.PixelFormat.Format32bppArgb)

    Using graphics As Graphics = graphics.FromImage(outputImage)
        graphics.PixelOffsetMode = PixelOffsetMode.HighQuality
        graphics.Clear(Color.White)
        graphics.DrawImage(images(0), New Rectangle(New Point(), images(0).Size), New Rectangle(New Point(), images(0).Size), GraphicsUnit.Pixel)
        graphics.DrawImage(images(1), New Rectangle(New Point(0, images(0).Height + 1), images(1).Size), New Rectangle(New Point(), images(1).Size), GraphicsUnit.Pixel)
        graphics.DrawImage(images(2), New Rectangle(New Point(0, images(0).Height + images(1).Height + 1), images(2).Size), New Rectangle(New Point(), images(2).Size), GraphicsUnit.Pixel)
    End Using

    Return outputImage
End Function