Better Form

[Wayne Wengert]

I have an XML document (see below) in which I have a <COMPANY> element that,
in turn, contains other elements. Based on an example I saw somewhere I
coded it as shown in the sample. In purusing other posts and books I see
alternatives such as:

<COMPANY name="My Comapny Name
<City>Podunk</City>
.................

and another alternative:

<COMPANY>
<Name>My Company Name</Name>
<City>Podunk</City>
.................

What are the pros and cons of these approaches? From what I've seen, .NET
creates the format shown in the sample belw when you convert a dataset to
XML

Wayne

================= sample xml ================
<?xml version="1.0"?>
<root xmlns="http://tempuri.org/SC308Hayward CG7.xsd">
<COMPANY>My Company Name
<City>Podunk</City>
<State>IA</State>
<Contact>Joness, Jimmy</Contact>
.............
</COMPANY>
............
</root>

[Jaga]

A) If you have a DataTable "COMPANY" and you create the column "Name" with
ColumnMapping = MappingType.Element, the DataSet creates an XML file like
this:
<COMPANY>
<Name>My Company Name</Name>
<City>Podunk</City>
...
</COMPANY>

B) If you create the column with ColumnMapping = MappingType.Attribute, the
XML file will be like this:
<COMPANY Name="My Company Name">
<City>Podunk</City>
...
</COMPANY>

C) If you create the column with ColumnMapping = MappingType.Hidden, the XML
file will be like this: (the column "Name" is hidden)
<COMPANY>
<City>Podunk</City>
...
</COMPANY>

D) If you create the column with ColumnMapping = MappingType.SimpleContent,
the XML file will be like this:
<COMPANY City="Podunk"...>My Company Name</COMPANY>
(COMPANY can't have elements, only attributes beside the SimpleContent, City
and other columns must have MappingType.Attribute. Don't use your sample
xml)
If you read the XML files back, by A) and B) you get the same DataSet
(except ColumnMapping). By C) you has no column "Name", by D) you has a
column "COMPANY_Text" instead of "Name"

If the DataSet has a flat hierarchie or the DataTable has many columns, I
prefer A)
If the DataSet has a deep hierarchie or the DataTable has few columns, or
the table has subtables (elements with complex type), I prefer B). For a
computer it doesn't matter, only if people read the XML file.

What about performance? Has anybody tested A) versus B) ?

IF you use an XSD schema:
By objects with complex type you have to use elements, by objects with
simple type you can use generally attributes, if you need a special order
than use however a sequence with elements.
Jaga

[Wayne Wengert]

Thanks for all that information Jaga

Wayne

"Jaga" <ja***@web.de> wrote in message
news:OC**************@tk2msftngp13.phx.gbl...

A) If you have a DataTable "COMPANY" and you create the column "Name" with
ColumnMapping = MappingType.Element, the DataSet creates an XML file like
this:
<COMPANY>
<Name>My Company Name</Name>
<City>Podunk</City>
...
</COMPANY>

B) If you create the column with ColumnMapping = MappingType.Attribute, the XML file will be like this:
<COMPANY Name="My Company Name">
<City>Podunk</City>
...
</COMPANY>

C) If you create the column with ColumnMapping = MappingType.Hidden, the XML file will be like this: (the column "Name" is hidden)
<COMPANY>
<City>Podunk</City>
...
</COMPANY>

D) If you create the column with ColumnMapping = MappingType.SimpleContent, the XML file will be like this:
<COMPANY City="Podunk"...>My Company Name</COMPANY>
(COMPANY can't have elements, only attributes beside the SimpleContent, City and other columns must have MappingType.Attribute. Don't use your sample
xml)
If you read the XML files back, by A) and B) you get the same DataSet
(except ColumnMapping). By C) you has no column "Name", by D) you has a
column "COMPANY_Text" instead of "Name"

If the DataSet has a flat hierarchie or the DataTable has many columns, I
prefer A)
If the DataSet has a deep hierarchie or the DataTable has few columns, or
the table has subtables (elements with complex type), I prefer B). For a
computer it doesn't matter, only if people read the XML file.

What about performance? Has anybody tested A) versus B) ?

IF you use an XSD schema:
By objects with complex type you have to use elements, by objects with
simple type you can use generally attributes, if you need a special order
than use however a sequence with elements.
Jaga