MACROMEDIA COLDFUSION 5-DEVELOPING Manual do Utilizador descarregar pdf (Página 38)

ColdFusion MX 7 Getting Started Experience Tutorial Page 38 of 47

The cfif tag in this case translates to “if the current row being processed from the artwork query result set gives a

remainder of 1 after it is divided by 3, print a tr tag to the HTML.”

Using conditional processing with arithmetic operations is a powerful tool for your ColdFusion applications.

19. Add conditional statements around both the opening tr and the ending tr tags, as the following code shows:

<tr>

</cfif>

<strong>#artwork.artName#</strong><br>

Artist: #artwork.firstName# #artwork.lastName#<br>

Price: #artwork.price#<br>

#artwork.mediaType# - #artwork.description#<br>

<font color="##FF0000">#artwork.isSold#</font>

</td>

</tr>

</cfif>

</cfoutput>

</table>

Learning Point: Rules for using the Number signs

The artwork.currentRow variable does not need to be surrounded by number signs (#) when it is inside a cfif tag.

You can think of the use of number signs as necessary when it’s potentially unclear to ColdFusion what is a variable and

what is not.

Consider these rules:

• Number signs are necessary between beginning and ending cfoutput tags, because variables are intermingled with

plain text and HTML tags, and ColdFusion MX 7 needs to be told what to evaluate and what not to evaluate.

• Number signs are not necessary inside a cfif tag, because ColdFusion knows to only expect ColdFusion variables

and expressions there.

• Number signs are necessary between beginning and ending cfif tags because, like with cfoutput tags, variables

are intermingled with plain text and HTML tags.

• Number signs are sometimes necessary in a tag’s attribute values, as in the case of <cfdump var="#artwork#">,

to clarify to ColdFusion that you want the value treated as a variable rather than a literal string.

In the last two bullets, a distinction is made between variables between tags and variables inside a tag’s attributes.

20. Save and browse the page, and then view the page source.

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