Exception

>

Listing 26:

 The Exception element content 2 in XML content

The client can parse the Exception element in Listing 25, these are two elements with 

same element tag name 

Format

 in this node 

Exception

, which have different element 

contents: 

WMS_XML

  and 

INIMAGE

.  But  when  the  parser  meets  the 

Exception

element node  in Listing 26,  it doesn

'

t work. Because the Exception element node  in 

Listing 26 has different structure, the element contents in the Listing 25 before, now 

change  their  form  to two  new  elements  in  the 

Forma

t  element  node. The  parser  can 

not  recognize  these  two  new  elements  as  the  content  of  the 

Format

  element.    The 

element  contents: 

WMS_XML

  and 

INIMAGE

  now  become  tag  name  of  elements.  If 

we still want to parse the element  in  Listing 26, new codes  must be written point to 

structure  in  Listing  26.  Maybe  some  method  will  be  used  later,  and  the  parser  can 

parse all of the GetCapabilities XML documents that with similar DTD. 

4.2.2.2 

Dynamically load the image   

Current application can display the area that users select, but if the users pan it and the 

screen boundary encroaches the view box boundary of the image, the map outside of 

the  view  box  boundary  can  not  be  displayed  dynamically.  For  raster  image,  preload 

image as byte array can solve the problem. 

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