[SalesForce] Currency Format in Visualforce page

You will have to write a java script function that will append , in your value. You can use below java script function -

function addCommas(nStr)
{
    nStr += '';
    x = nStr.split('.');
    x1 = x[0];
    x2 = x.length > 1 ? '.' + x[1] : '';
    var rgx = /(\d+)(\d{3})/;
    while (rgx.test(x1)) {
    x1 = x1.replace(rgx, '$1' + ',' + '$2');
    }
    return x1 + x2;
}

Use below code to override inner HTML of component -

document.getElementById('elementID').innerHTML = addCommas(Value);

It is sent to salesforce as a name,value pair. If it doesn't have a name, it isn't available. It is not required because <apex:param> has other uses to like in <apex:outputText>. The value is therefore the only required field.