I volontari di MDN non hanno ancora tradotto questo articolo in Italiano. Registrati per tradurlo tu.
Summary
The Document.readyState property of a document describes the loading state of the document.
Values
The readyState of a document can be one of following:
- loading
- The
documentis still loading. - interactive
- The document has finished loading and the document has been parsed but sub-resources such as images, stylesheets and frames are still loading.
- complete
- The document and all sub-resources have finished loading. The state indicates that the
loadevent is about to fire.
When the value of this property changes a readystatechange event fires on the document object.
Syntax
var string = document.readyState;
Examples
Different states of readiness
switch (document.readyState) {
case "loading":
// The document is still loading.
break;
case "interactive":
// The document has finished loading. We can now access the DOM elements.
var span = document.createElement("span");
span.textContent = "A <span> element.";
document.body.appendChild(span);
break;
case "complete":
// The page is fully loaded.
console.log("The first CSS rule is: " + document.styleSheets[0].cssRules[0].cssText);
break;
}
readystatechange as an alternative to DOMContentLoaded event
// alternative to DOMContentLoaded event
document.onreadystatechange = function () {
if (document.readyState === "interactive") {
initApplication();
}
}
readystatechange as an alternative to load event
// alternative to load event
document.onreadystatechange = function () {
if (document.readyState === "complete") {
initApplication();
}
}
readystatechange as event listener to insert or modify the DOM before DOMContentLoaded
// early manipulation of the document <body> using an external script
var bootstrap = function(evt){
if (evt.target.readyState === "interactive") { initLoader(); }
else if (evt.target.readyState === "complete") { initApp(); }
}
document.addEventListener('readystatechange', bootstrap, false);
Specification
| Specification | Status | Comment |
|---|---|---|
| WHATWG HTML Living Standard The definition of 'Document readiness' in that specification. |
Living Standard | |
| HTML5.1 The definition of 'Document readiness' in that specification. |
Working Draft | |
| HTML5 The definition of 'Document readiness' in that specification. |
Recommendation | Initial specification. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | 5.0 | 4.0 | 8.0[1] 9.0[2] | 11.0[1] | 5.0 |
| Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | 2.2 | 4.0 | 9[2] | 11.0[1] | 5.0 |
[1] Only support 'complete'. Opera Presto fire 'complete' late after the 'load' event (in an incorrect order as per HTML5 standard specification).
[2] Internet Explorer 9 and 10 have bugs where the 'interactive' state can be fired too early before the document has finished parsing.
See also
readystatechangeeventDOMContentLoadedeventloadevent