How to draw a chart with OWC in asp.net (1)

How to draw a chart with OWC in asp.net (1)
I. Overview
Second, set up the chart engine
III. Licensing issues for OWC
Iv. operating mechanism of OWC
V. Install OWC 10 on the Web server
Six, OWC Programming mode
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I. Overview
When you develop an application, you often encounter situations where you must provide an interactive diagram. For example, you might be developing an application that manages sales and product data, the data is stored on a SQL Server database, and applications allow users to add data and update existing data, but in addition to these features, customers require applications to visually describe data in the form of pie, column, or xy (scatter) charts.
In Windows desktop applications, such requirements never become a problem, and there are too many graphics libraries and drawing components to choose from. But for Web applications, the problem becomes much more complicated. To draw a chart in a Web application, options include:
Client
With various ActiveX components, it is entirely possible for a Web browser to achieve the functionality of a "rich" Windows client program. The disadvantage is that client-side settings are complicated, requiring the release of client software, which typically calculates the license cost per client basis. In addition, non-MS Windows/ie clients are generally difficult to run.
Server side:
Use the server-side code that runs on the Web server to dynamically generate the chart and send it to the client as a GIF or JPG graphic. The advantage of this approach is that the client only needs a standard browser. The disadvantage of the client-side technology is that the graphics are poorly interactive (you cannot scale, scroll unless you submit a new request to the server). Many map sites (such as mapquest.com) use this technique in large numbers. Note that map graphics are not stored on the Web server, but are generated dynamically from the map database when a user makes a request.
This paper mainly discusses how to use the server-side graph rendering technology to provide graphics function in ASP.net Web pages, specifically, this paper analyzes how to generate a scatter graph by using the data stored in MS SQL database.
Second, set up the chart engine
If you want to draw a chart in a asp.net application, you must have a suitable diagram engine. Asp. NET has a built-in graphics tool library, that is, System.Drawing namespace GDI +, can be used to create simple pie, column, line chart, etc., but it is a low-level API, not to draw the graphics engine, especially not suitable for the drawing of complex charts.