ASP.NET and GDI+
Working with GDI can be tricky on the web, this tutorial is a basic introduction for people who needs to draw images on the fly. Here we cover drawing text and lines.
Charting in .Net using SVG
When graphic needs exceed the capabilities of third-party components, the programmer needs tools for generating customized charts. This article focuses on generating customized charts using the powerful combination of .Net and SVG.
Create Charts Using MSChartActive X Controls in ASP.NET
Displaying graphical charts in Web pages is not an easy task compared to rendering the raw data in an html table, but the effort of creating beautiful charts is worth it as a professional looking chart can make users happy and more important, impress management. With ASP.NET, we can create charts using classes in the System.Drawing namespace. Those classes could be used to create and edit images in a variety of formats, we can quite easily create an ASP.NET Web page that, when requested, generates a chart based on database information and send the image to the requesting client's browser. Since this method sounds so decent, why still consider using Active X control?
Create Snazzy Web Charts and Graphics On the Fly with the .NET Framework
Knowledge workers can understand data more effectively when raw numbers are presented in a graphical format. This is especially true when displaying database information on a Web page, where a simple chart can make the difference between a dry presentation and a vivid data source. In the past, creating dynamic, data-based charts on the fly in ASP required purchasing a third-party, image-generating COM component. Now with ASP.NET, developers can access the .NET Framework's drawing classes directly with C# to create dynamic images and charts.
Creating Graphics On-the-Fly in ASP.NET
Creating graphic for use in your web page is a snap in .NET. In this example I will be using VB.NET to create a graphic file for use in a page. Since this graphic will be hosted in an Image server control you will have full access to placement, sizing and other properties.
Creating Images on the Fly with ASP.NET
Before the advent of the .Net framework, creating images on the fly for a web browser was a tedious task. Now, thanks to the .Net framework, creating images on the fly is a simple task. This article will provide the reader with the fundamentals necessary to start developing dynamic images with the .Net framework.
Creating Line, Bar, and Area Charts using ASP.NET
Part 3 of a Multipart Series - In this tutorial we will learn how to create line, bar, and area PNG charts on the fly and incorporate them in our website statistics application. Specifically, we will create area charts of daily visits and page views for the last 12 months, and display them in the reports section of our application. Again, all code has been explained in detail, and is available for download.
Creating Validation Images On-The-Fly with GDI+
Developers, like myself, can spend many hours with a graphics tool trying to design graphical buttons for a Web site. However, there is a technique that enables you to specify things like, font, size, colour etc and create buttons/labels on-the-fly! Were going to look at an example where creating dynamic images can prove very useful and is in use by many sites already.
Developing An Image Upload Web Service
ASP.NET Web Services provide 'Web callable' functions based on industry standards like HTTP, XML and SOAP. Since Web Services heavily rely on XML, all the data that is passed to and returned from a Web Service must be plain text. However, in certain applications we do need to pass binary data. Say for example I want to pass images from my Web form to a Web Service to save in some central repository and then retrieve them back. Does this mean that Web Services cannot be used for such data transfer?
Dynamic Image Output Component in .NET
This article discusses how to use a single line of code (via a component call) to output the contents of an image residing on the server's hard drive.
Dynamic thumbnail images from ASP.NET
This sample code is an IHttpHandler implementation that reads a JPG from the filesystem and dynamically generates a thumbnail sized version of the image and emits that to the response stream. What I like about this approach is that you don't need to create a file on the filesystem for the thumbnail as it's all done in memory.
Generating graphics on the fly
Something that cannot be done in ASP without support by an external component is dynamic creation of graphics - be it a diagram, a banner or just a simple graphical counter. This fortunately has changed for ASP+ - using built-in means, graphics can be created dynamically and sent to the client with a maximum of configurability and ease.
Obtaining Image Information on your own
A frequent problem in uploading image files is that the size (width, height) isn't known and that consequently you have to determine them on your own.
Optimizing Color Quantization for ASP.NET Images
Describes how to quantize (recolor) dynamically generated images for ASP.NET pages in order to overcome a limitation of GDI+ in the .NET Framework versions 1.0 and 1.1. This article presents two methods of color depth reduction on images.
Serving Images from .NET Assemblies
Most if not all Web sites require images for their user interface, and these are usually stored on disk. This article shows how images can be served from an assembly, which can avoid the proliferation of numerous files on disk, can simplify installation and configuration of the Web server, and can increase the security of those images.
Uploading, determining size, width and height and resizing image files with ASP.NET
Comprehensive tutorial on uploading image files, determing size
( in bytes ), type ( bmp, jpg, gif ), width and height ( in
pixels ) of these images, imposing restrictions to allow images
of only certain size, width and height to get uploaded and to
resize ( create thumbnails of ) these images.
Articles
