加载时不调用JavaScript函数

Question

I am using a javascript function that is supposed to invoke on page load complete (like JQuery's function) heres what it looks like:

<script>
var ready = function(fn) {

    // Sanity check
    if (typeof fn !== 'function') return;

    // If document is already loaded, run method
    if (document.readyState === 'complete') {
        return fn();
    }

    // Otherwise, wait until document is loaded
    // The document has finished loading and the document has been parsed but sub-resources such as images, 
    //stylesheets and frames are still loading. The state indicates that the DOMContentLoaded event has been fired.
    document.addEventListener('complete', fn, false);
};

ready(function() {
    alert(lang);
    Load(@Model.Language); //<--this is what I want called

    });
</script>

------->MVC Stuff<-------

 function Load(lang) {


 switch (lang) {
   case 'Other':
        BuildBox("text/text");
    case 'CSharp':
        BuildBox("text/x-csharp");
        break;

}

When I set the breakpoint at the Assignment from the model, we're hitting it. However, nothing else ever happens (including the alert box. I'm not sure why it is not executing the function fully upon load.

Answer 1

This works:

function ready(fn) {

  // Sanity check
  if (typeof fn !== 'function') return;

  // If document is already loaded, run method
  if (document.readyState === 'complete') {
    fn();
  }

  // Otherwise, wait until document is loaded
  // The document has finished loading and the document has been parsed but sub-resources such as images, 
  //stylesheets and frames are still loading. The state indicates that the DOMContentLoaded event has been fired.
  document.addEventListener('readystatechange', function () {
    if (this.readyState === 'complete') fn();
  }, false);
}

ready(function() {
  alert("loading complete");
});

Answer 2

I suggest you to use this.

    (function () {
    var x = "Hello!!";      // I will invoke        myself
})();

The parantheses(); after the anonymous function is calling the function itself. And you can impliment document ready event like this.

    document.addEventListener('DOMContentLoaded', function() {
   // ...
});