I am trying to find out if the following is the correct usage and is valid across all types of browsers. I have tried the html entity converted method in IE8 and the JavaScript executed perfectly without any errors.

One way to embed inline JavaScript in an HTML tag would be to use literal charactures, but this is considered invalid xhtml markup.

<button onclick='alert("1 > 0 && 0 < 1 = "+(1 > 0 && 0 < 1 ? "true" : "false"));'>Test Me 1</button>

When I use html entities for certain charactures, this works in IE8 and the JavaScript still works.

<button onclick="alert(&quot;1 &gt; 0 &amp;&amp; 0 &lt; 1 = &quot;+(1 &gt; 0 &amp;&amp; 0 &lt; 1 ? &quot;true&quot; : &quot;false&quot;));">Test Me 2</button>

Will the second attempt work across all browsers?

You could escape the quotes with \.

<button onclick="alert(\"1 > 0 && 0 < 1 = \"+(1 > 0 && 0 < 1 ? \"true\" : \"false\"));">Test Me 1</button>

Single quotes would also work here.

EDIT: It's not working as expected... Can you do that kind of thing using JS? Try just an if statement.

EDIT2: This works for me:

<button onclick="if(1>0){o='true';}else{o='false';}alert(o);">Test Me 1</button>

But I'm not sure if that's what you're going for.

I would think escaping quotes would not work in html markup and it would break. Also you have other illegal chars such as < and >

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I'm not looking to replace the js code, but seeing if the method is correct and compatable accross browsers
</edit>