Auto populate select box

问题

I am trying to auto populate a select box using Jquery and JavaScript.

I done some searching and came across this question and followed the advice of the selected answer.

I originally set up a jsFiddle to illustrate my problem: http://jsfiddle.net/GJdBR/

After receiving some advice on answers below I created a new jsfiddle and it worked. http://jsfiddle.net/2UbqP/

However, on my computer I am using a clean install of windows 7, all I have done so far, is install chrome, apanta and xampp. I go to localhost/website and the site comes up, however the js functionality doesn't work, the select box isn't being filled with the var even though I proved the code is correct because of the jsfiddle above.

I am getting an error on this:

$(document).ready(function() {
    populateTranslationOptions();
});

The error reads:

Uncaught SyntaxError: Unexpected token ILLEGAL

回答1:

You have several problems in your code. check this

function populateTranslationOptions ()
{
    var translationOptions = ["Egyptian Hieroglyphs", "Al Bhed (Final Fantasy X)", "Futurama"];
    $.each(translationOptions ,function(i,value) {   
        $('#translationOptions')
            .append($("<option></option>")
            .attr("value",value)
            .text(value)); 
    });
}

$(document).ready(function() {
   populateTranslationOptions();
 });

Problems in your code:

$.each syntax is wrong

$.each(translationOptions (value)) {

Should be

$.each(translationOptions ,function(i,value) {

You were not calling the function populateTranslationOptions; doesnt call the function populateTranslationOptions(); does.

Working Fiddle

回答2:

For arrays, $.each is unnecessary. You can use a simple loop rather. Like as follows -

function populateTranslationOptions()
{
    var translationOptions = ["Egyptian Hieroglyphs", "Al Bhed (Final Fantasy X)", "Futurama"];
    for (var i = 0; i < translationOptions.length; i++) {
        $('#translationOptions')
            .append('<option value="' + translationOptions[i] + '">' + translationOptions[i] + '</option>');
    };
}

$(document).ready(function() {

   populateTranslationOptions();
 });

回答3:

$.each(translationOptions, function (index, value) {   
        $('#translationOptions')
            .append($("<option></option>")
            .attr("value",value)
            .text(value)); 
    });

You've tried

$.each(translationOptions, (value) )

it's wrong, because correct structure is $.each(mapData, callbackFunction), here mapData means Object or Array.

And next issue is:

 $(document).ready(function() {
   populateTranslationOptions;
 });

It should ne

$(document).ready(function() {
   populateTranslationOptions(); // you missed () here
 });

Mind that, populateTranslationOptions doesn't call a function, so to call a function you need to populateTranslationOptions().

DEMO

One important note

The () after a function means to execute the function itself and return it's value. Without it you simply have the function, which can be useful to pass around as a callback.

Related refs:

$.each()
call javascript function with/without parenthesis

来源：https://stackoverflow.com/questions/10872714/auto-populate-select-box

标签

javascript

jquery

html-select