<!DOCTYPE html>
<html>

<!-- 
    Our second SJAT example...that now checks
    to see if its request succeeded
-->

<!--
    by: Sharon Tuttle (based on example
	 in Ch. 12 of course text)
    last modified: 5-6-13
-->

<head>  
    <title> SJAT Example 2 </title>
    <meta charset="utf-8" />

    <script type="text/javascript">

        // when button with id of "load" is clicked,
        //    I hope to synchronously fill a textarea

        window.onload =
            function()
            {
                var loadButton = 
                    document.getElementById("load");
                loadButton.onclick = loadClick;
            };

        // signature: function: loadClick: void -> void
        // purpose: expects nothing, and returns 
	    //     nothing, BUT hopefully has the side-
	        //     effect of filling the textarea with
		    //     id of "output" with the contents
		        //     of the local file notes.txt
        //     OR with error information if it
        //     cannot

        function loadClick()
        {

            var ajax = new XMLHttpRequest();
            ajax.open("GET", "notes.txt", false);
            ajax.send(null);
            var outputTextArea = 
                document.getElementById("output");

            // fill output textarea either with
	            //    the contents of notes.txt OR
		            //    with error info
            // (status of 200 is success!)

            if (ajax.status != 200)
            {
                outputTextArea.value =
                    "Error fetching text of " +
                    "notes.txt:\n" +
                    ajax.status + " - " +
                    ajax.statusText;
            }
            else
            {
                outputTextArea.value = 
                    ajax.responseText;
            }
        }   
    </script>

</head> 

<body> 
    <noscript>
    <p>
    Your browser does not support JavaScript, or
    has it disabled; this page will not behave as
    it should.
    </p>
    </noscript>

    <h1> SJAT Example 2 </h1>

    <!-- feels odd -- but there's NOT a form here! -->
 
    <p> 
        <textarea name="notes" rows="5" cols="30"
                  id="output">
        </textarea>
    </p>

    <p>
    <button id="load"> Load </button>    
    </p>

    <hr />   

    <p>
        <a href="http://validator.w3.org/check/referer">
        Validate this HTML5 page
        </a>
    </p>

    <p>
        For full credit, this page must also pass the tests at
        <a href="http://lint.brihten.com/html/">
        http://lint.brihten.com/html/ </a> when its URL is
        entered (and without modifying the default options).
    </p>

    <p>
        <a href=
           "http://jigsaw.w3.org/css-validator/check/referer?profile=css3">
            <img src="http://jigsaw.w3.org/css-validator/images/vcss" 
                 alt="Valid CSS3!" height="31" width="88" />
        </a>
    </p>

</body> 
</html>