JavaScript验证问题

Question

In the following code document.write("<h1>" + Date() + "<\\/h1>"); I need to use \\ in the closing h1 tag to validate my HTML page. Whats the purpose of using \\ in the tag.

Answer 1

The backslash character is usually used to escape "special" characters. You shouldn't need it in there.

Answer 2

You shouldn't be writing DOM elements using document.write , this overwrites any existing DOM elements that were in the HTML document.

The second slash (backslash) that you've used shouldn't be needed. Take a look at this example for both of my points:

http://jsfiddle.net/SrQKt/7/

Answer 3

In JavaScript, only /script needs to be escaped \\/script

In HTML validation move the JS to an external file to allow validation.

Using innerHTML is sligthly better - DOM manipulation will also do the job inline or in external files:

var header = document.createElement("h1");
header.appendChild(document.createTextNode(new Date()))
someContainer.appendChild(header);

for example

Answer 4

There is no formal error in your JavaScript code. The problem is probably that you have it inside an HTML document, in a script element, and then </h1> may become a problem (depending on HTML version and software used). At the HTML level, the \\ breaks the construct so that it won't be parsed as an end tag. In a JavaScript literal, \\/ means just the same as / (you can “escape” a normal character, too).