ASP.NET

Chart Control

• User control (inherits System.Web.UI.UserControl)
  • pie chart
  • random "pie" parts colors (white background)
  • dynamically created images (use HTTP Handler, saving images do a disk is not allowed)
  • description of the data located on each "pie" fragment
  • images are provided to a browser as a PNG image files
  • author could assume that the sum of all the data is 100.0%
• Obligatory properties
  • DataSource - both DataSet object of DataTable object must be allowed
  • DataMember - source table name in the case when DataSource is a DataSet type
  • DataTextField - name of the column with data description
  • DataValueField - name of the column with data
  • Size - size of the chart image
• Example control usage - ASP.NET 2.0 Web Site
  
  • 2 controls on the default web form
  • one using DataSet as a DataSource - data loaded from this file
  • another one uses dynamically created DataTable data source

• Hints:
  • UserControl.Cache
  • Image.Save(Stream, ImageFormat)
  • Page.MapPath()

• Approximate points:
  • user control
    • DataSet data source: 1.0
    • DataTable data source: 1.0
    • pie chart: 2.5
    • data description on the image: 1.5
    • HTTP Handler: 2.0
  • example application: 2.0

• Links for uploading:
  • Solutions
  • Corrections