How do I load a javascript file dynamically? [duplicate]

Question

I have this code:

    <script type="text/javascript">
    function js() {
        var getJs = document.getElementById("jogo");

        if (JS == true) { //if button JS is pressed - it is correct?

            < script type = "text/javascript"
            src = "file1.js" >


        } else < script type = "text/javascript"
        src = "file2.js" >
</script>
}
</script>

it doesn't work. I gave two buttons, if the first is pressed, file1.js should be loaded. In case the second one is pressed, file2.js should be loaded.

How can I do that?

Answer 1

You cannot embed HTML in Javascript in that way. Basically, what you want is to embed a script element, pointing to a certain javascript file when clicking a button. That can be done with combining events with DOM:

<script type="application/javascript">
function loadJS(file) {
    // DOM: Create the script element
    var jsElm = document.createElement("script");
    // set the type attribute
    jsElm.type = "application/javascript";
    // make the script element load file
    jsElm.src = file;
    // finally insert the element to the body element in order to load the script
    document.body.appendChild(jsElm);
}
</script>
<button onclick="loadJS('file1.js');">Load file1.js</button>
<button onclick="loadJS('file2.js');">Load file2.js</button>

Answer 2

Try this on for size: Dynamically Load JS

function loadjscssfile(filename){
  var fileref=document.createElement('script')
  fileref.setAttribute("type","text/javascript")
  fileref.setAttribute("src", filename)
 if (typeof fileref!="undefined")
  document.getElementsByTagName("head")[0].appendChild(fileref)
}

loadjscssfile("myscript.js") //dynamically load and add this .js file

Answer 3

JavaScript:

function loadScript(url)
{
    document.body.appendChild(document.createElement("script")).src = url;
}
function loadDefaultScript()
{
    loadScript("http://mysite.com/file1.js");
}
function loadAlternateScript()
{
    loadScript("http://mysite.com/file2.js");
}

HTML:

<input type="button" onclick="loadAlternateScript()" value="Alternate" />
<input type="button" onclick="loadDefaultScript()" value="Default" />

Answer 4

You can use this function this will work perfectly

function loadjscssfile(filename, filetype){
 if (filetype=="js"){ //if filename is a external JavaScript file
  var fileref=document.createElement('script')
  fileref.setAttribute("type","text/javascript")
  fileref.setAttribute("src", filename)
 }
 else if (filetype=="css"){ //if filename is an external CSS file
  var fileref=document.createElement("link")
  fileref.setAttribute("rel", "stylesheet")
  fileref.setAttribute("type", "text/css")
  fileref.setAttribute("href", filename)
 }
 if (typeof fileref!="undefined")
  document.getElementsByTagName("head")[0].appendChild(fileref)
}

loadjscssfile("myscript.js", "js") //dynamically load and add this .js file
loadjscssfile("javascript.php", "js") //dynamically load "javascript.php" as a JavaScript file
loadjscssfile("mystyle.css", "css") ////dynamically load and add this .css file

Answer 5

Via Jquery:

 var getJSfile = function(src) {
            var jsfile = $("<script type='text/javascript' src='"+src+"'>");
            $("head").append(jsfile); 
        }; 

    getJSfile ("home.js");