有没有优化多个if，else if，else语句的方法？

Question

Here's my code, is there anyway to somehow loop through the if, else if and else statements to dynamically populate them somehow (without so many statements, or is this considered good practice)?

$('input').each( function () {

    var self = $(this)

    if ( self.attr( 'type' ) === 'email' && supportsInputType ( 'email' ) ) {
            self.data( 'fallback', 'email' )
    } else if ( self.attr( 'type' ) === 'url'  && supportsInputType ( 'url' ) ) {
            self.data( 'fallback', 'url' )
    } else if ( self.attr( 'pattern' ) && supportsAttr ( 'pattern' ) ) {
        self.data( 'fallback', 'pattern' )
    }

})

I've omitted my other functions as concentrating on the if/else etc. Thanks for any advice.

Answer 1

If you make supportsInputType properly handle any type, you could just do something like this:

$('input[type]').each(function() {
    var $this = $(this);

    if (this.type !== $this.attr('type')) {
        $this.data('fallback', type);
    }
});

Answer 2

I would try to craft a selector that grabs the inputs by attribute straight away and get rid of supportInputType . Something like this (untested):

var attrs = ['type=email','type=url','pattern'];

$.each(attrs, function(i,attr) {
  $('input['+ attr +']').data('fallback', attr.replace(/.+=/,''));
});

That should probably work with your current code.