Formatting Negative Numbers with Parentheses

Question

Formatting numbers on a VF page, but I do a bunch of processing the Apex Class, so I would rather return the formatted String value from the controller.

I am doing something like this, but I just want the second number to appear as "(1500)" rather "-1500" Getting lost in the Message Format docs, so hoping someone can guide me in the right direction...

List<String> args = new String[]{'0','number','###,###,###'};
system.debug('Positive' + String.format(  ( (1000) - (500.50)  ).round().format(), args) );
system.debug('Negative' + String.format(  ( (-1000) - (500.50)  ).round().format(), args) );

Answer 1

Typically it's best to leave the formatting to the visualforce page and leave the controller to handle the model/controller side of things. You can easily do this in the Visualforce page and if you're using it in a lot of places just put it in a component you can reference all over the place.

<apex:outputText value="{0, number, ###,###,###}" rendered="{!value >= 0}">
    <apex:param value="{!value}"/>
</apex:outputText>
<apex:outputText value="({0, number, ###,###,###})" rendered="{!value < 0}">
    <apex:param value="{!value * -1}"/>
</apex:outputText>

Answer 2

While Ralph Callaway's example is technically correct, it can be simplified.

There is no need for conditional rendering of the <apex:outputText> elements, or multiplying the value by -1. Instead we can use a subpattern for the negative number format.

From Java docs:

A DecimalFormat pattern contains a positive and negative subpattern, for example, "#,##0.00;(#,##0.00)". Each subpattern has a prefix, numeric part, and suffix. The negative subpattern is optional; if absent, then the positive subpattern prefixed with the localized minus sign ('-' in most locales) is used as the negative subpattern. That is, "0.00" alone is equivalent to "0.00;-0.00". If there is an explicit negative subpattern, it serves only to specify the negative prefix and suffix; the number of digits, minimal digits, and other characteristics are all the same as the positive pattern. That means that "#,##0.0#;(#)" produces precisely the same behavior as "#,##0.0#;(#,##0.0#)".

By using ; to separate both the positive and negative subpatterns we can use a single <apex:outputText> to render both positive and negative values.

<apex:outputText value="{0, number, ###,###,###;(###,###,###)">
    <apex:param value="{!value}"/>
</apex:outputText>

When the value is positive, the subpattern ###,###,### is used and when the value is negative the subpattern (###,###,###) is used.

Answer 3

Try creating a method in the controller to return the formatted string of a decimal:

public string negToParentheses (decimal d){
    if(d<0)
        return '('+string.valueof(-d)+')';
    return string.valueof(d);
}