JavaScript equivalent to printf/String.Format

Question

I\'m looking for a good JavaScript equivalent of the C/PHP printf() or for C#/Java programmers, String.Format() (IFormatProvider for .

Answer 1

I have a slightly longer formatter for JavaScript here...

You can do formatting several ways:

• String.format(input, args0, arg1, ...)
• String.format(input, obj)
• "literal".format(arg0, arg1, ...)
• "literal".format(obj)

Also, if you have say a ObjectBase.prototype.format (such as with DateJS) it will use that.

Examples...

var input = "numbered args ({0}-{1}-{2}-{3})";
console.log(String.format(input, "first", 2, new Date()));
//Outputs "numbered args (first-2-Thu May 31 2012...Time)-{3})"

console.log(input.format("first", 2, new Date()));
//Outputs "numbered args(first-2-Thu May 31 2012...Time)-{3})"

console.log(input.format(
    "object properties ({first}-{second}-{third:yyyy-MM-dd}-{fourth})"
    ,{
        'first':'first'
        ,'second':2
        ,'third':new Date() //assumes Date.prototype.format method
    }
));
//Outputs "object properties (first-2-2012-05-31-{3})"

I've also aliased with .asFormat and have some detection in place in case there's already a string.format (such as with MS Ajax Toolkit (I hate that library).