Updated on Kisan Patel
This tutorial will explain you how to crop image using C# System.Drawing class in ASP.NET web application?
Here, we need to use Bitmap.Clone method as seen in below method to creates a copy of the section of this Bitmap defined by Rectangle structure and with a specified PixelFormat enumeration.
public static Image CropImage(Image img, Rectangle cropArea)
{
var bmpImage = new Bitmap(img);
var bmpCrop = bmpImage.Clone(cropArea, bmpImage.PixelFormat);
return bmpCrop;
}
So Lets First create New ASP.NET web application and add the below line of code to Default.aspx page.
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebCropImage.Default" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>ASP.NET Image Crop Demo</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<p>
<label>Select the file: </label>
<asp:FileUpload ID="file_upload" runat="server" />
</p>
<p>
Height:
<asp:TextBox ID="txt_Width" runat="server"></asp:TextBox>
Width:
<asp:TextBox ID="txt_Height" runat="server"></asp:TextBox>
</p>
<p>
<asp:Button ID="btn_CropImage" runat="server" Text="Crop Now" OnClick="btn_CropImage_Click" />
</p>
</div>
</form>
</body>
</html>
Now, add the following code to default.aspx.cs class to crop the image using C# System.Drawing class.
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using Image = System.Drawing.Image;
namespace WebCropImage
{
public partial class Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
public static Image CropImage(Image img, Rectangle cropArea)
{
var bmpImage = new Bitmap(img);
var bmpCrop = bmpImage.Clone(cropArea, bmpImage.PixelFormat);
return bmpCrop;
}
protected void btn_CropImage_Click(object sender, EventArgs e)
{
string filename = System.IO.Path.GetFileName(file_upload.FileName);
file_upload.SaveAs(Server.MapPath("~/upload/") + filename);
//Get the height and width of Crop image
var w = Convert.ToInt32(txt_Width.Text);
var h = Convert.ToInt32(txt_Height.Text);
//Get the image
using (var bitmap = Image.FromFile(Server.MapPath("~/upload/") + filename))
{
var rectangle = new Rectangle();
//Set the position Centered to crop image from centered
var value = "Centered";
switch (value.ToString())
{
case "Centered":
var x = ((bitmap.Width - w) / 2);
var y = ((bitmap.Height - h) / 2);
rectangle = new Rectangle(x, y, w, h);
break;
//Crop Image from TopLeft Corner
default:
rectangle = new Rectangle(0, 0, w, h);
break;
}
using (var resized = CropImage(bitmap, rectangle))
{
//Save image into memory stream...
using (var ms = new MemoryStream())
{
resized.Save(ms, ImageFormat.Jpeg);
}
//Save the cropped Image file to "cropped" folder...
resized.Save(Server.MapPath("~/cropped/") + filename, ImageFormat.Jpeg);
}
}
}
}
}