[Zope] Help with dtml-let & dtml-if

[Ben Leslie]

Hi Andrew!

On Wed, 29 Mar 2000, Andrew Diller wrote:

> 
> Hello:
> 
> I'm not getting dtml-let. I use it to create a variable that I can access, correct?
> 
> Say I want to initialize a counter, and change it from 0 1 each iteration of a loop.
> 
> This will print out rows of a table with alternating background colors:
> 
> 
> <dtml-let x=0>
> </dtml-let>
> 
> <dtml-in "getElementsByTagName('book')" >
> 
> <dtml-if x==0>
> 	<tr bgcolor="DDEEAC">
> <dtml-else>
> 	<tr>
> </dtml-if>
> 
> 
> write out some html
> 
> </tr>
> 
> <dtml-if x==0>
> 	<dtml-let x=1>
> 	</dtml-let>
> <dtml-else>
> 	<dtml-let x=0>
> 	</dtml-let>
> </dtml-if>
> 
> </dtml-in>
> </table>
> </dtml-with>
> 


<dtml-let> tags only set that variable within the <dtml-let>context</dtml-let>
tags. 

The task you wish to do would much easily done using the variables set by
dtml-in. Eg <dtml-var sequence-index> will print out the 'count' if you like
for the list.

<dtml-if sequence-start> </dtml-if> (from memory?) will evaluate if it is
the first iteration of the loop.

<dtml-if sequence-even> and <dtml-if sequence-odd> will evaluate odd and
even iterations of the loop, which is what it apears you want todo.

Check out the zope quick reference document for documentation on
this 

http://www.zope.org/Members/ZQR.

Cheers,

Benno