JQuery append to select with an array

问题

very simple but guess what, not for me. I have a comma separated list like this: Option1,Option2,Option3 that I want to append to a <select> so it becomes <select><option>Option1</option><option>Option2</option><option>Option3</option></select>

I can "split" the list like this (inside a function that gets the list):

var optionsarray = $(this).val().split(',');

    $(optionsarray).each(function(i){
        var seloption = '<option value="'+optionsarray[i]+'">'+optionsarray[i]+'</option>'; 
    });

But now how do I append seloption to my select list. If I put

$('#selecttoappendto').append('<option value="'+optionsarray[i]+'">'+optionsarray[i]+'</option>');

$('#selecttoappendto').append(seloption);

inside the each loop nothing happens. Take it outside the each I can append say optionsarray[0], or optionsarray[1] etc. but I cannot get to append optionsarray[i] which ever way I do it (inside or outside the each). Help please - thanks in advance

回答1:

Starting with an empty string, you can build a string in the loop usingt +=. Then .append() the string.

var optionsarray = $(this).val().split(',');

var seloption = "";

$.each(optionsarray,function(i){
    seloption += '<option value="'+optionsarray[i]+'">'+optionsarray[i]+'</option>'; 
});

$('#selecttoappendto').append(seloption);

or another option would be to build the elements separately, store them in a container, then append them from the container.

var optionsarray = $(this).val().split(',');

var temp_sel = $('<select>');

$.each(optionsarray,function(i){
    temp_sel.append('<option>',{text:optionsarray[i],
                                value:optionsarray[i]
                                });
});

temp_sel.children().appendTo('#selecttoappendto');

Fixed missing () after children.

回答2:

Here's what I wrote and use; it's a little faster than the solution user113716 gave, because you're skipping creating the temp select, all those appends to that temp select (even if it is a DOM fragment, it still takes some time), and you're also skipping the .children() find and unwrapping at the end for that final append.

// Appends multiple elements all at once; maintains chaining
$.fn.appendAll = function ($eleArr) {
    var numEles = $eleArr.length
    ,    $useEle = new $();
    if (numEles) {
        while (numEles--) {
            $useEle = $eleArr[numEles].add($useEle);
        }
        return $(this).append($useEle);
    }
};

// Prepends multiple elements all at once; maintains chaining
$.fn.prependAll = function ($eleArr) {
    var numEles = $eleArr.length
    ,    $useEle = new $();
    if (numEles) {
        while (numEles--) {
            $useEle = $eleArr[numEles].add($useEle);
        }
        return $(this).prepend($useEle);
    }
};

So:

var optsArr = $(this).val().split(','),
    $options = [],
    thisOption;

$.each(optsArr, function(i) {
    thisOption = '<option value="' + optsArr[i] + '">' + optsArr[i] + '</option>';
    $options.push($(thisOption));
});

$yourSelect.appendAll(optsArr);

I actually wrote those plugins for exactly this; doing it this way, I build a 1500+ option select in under 250 ms. :D

来源：https://stackoverflow.com/questions/4969754/jquery-append-to-select-with-an-array

标签

jquery

select

append

each