andersonba/a.html

## a.html
<!doctype html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>iframe A</title>
    <script>
      window.myDate = new Date();
      window.myString = new String('A');
    </script>
  </head>
  <body bgcolor="#e5edff">
    myDate = <span id="var1"></span><br />
    <strong>instanceof Date is <span id="val1"></span></strong>
    <hr />
    myString: <span id="var2"></span><br />
    <strong>instanceof String is <span id="val2"></span></strong>

    <script>
      window.myDate = new Date();
      document.getElementById('var1').innerText = window.myDate.toISOString();
      document.getElementById('val1').innerText = window.myDate instanceof Date;

      document.getElementById('var2').innerText = window.myString;
      document.getElementById('val2').innerText = window.myString instanceof String;
    </script>
  </body>
</html>

## b.html
<!doctype html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>iframe B</title>
    <script>
      window.myDate = new Date();
      window.myString = new String('B');
    </script>
  </head>
  <body bgcolor="#e5ffec">
    myDate = <span id="var1"></span><br />
    <strong>instanceof Date is <span id="val1"></span></strong>
    <hr />
    myString: <span id="var2"></span><br />
    <strong>instanceof String is <span id="val2"></span></strong>

    <script>
      window.myDate = new Date();
      document.getElementById('var1').innerText = window.myDate.toISOString();
      document.getElementById('val1').innerText = window.myDate instanceof Date;

      document.getElementById('var2').innerText = window.myString;
      document.getElementById('val2').innerText = window.myString instanceof String;
    </script>
  </body>
</html>

## index.html
<!doctype html>
<html lang="pt-bt">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Proof of concept: Frame boundaries</title>

    <script>
      var securityErrorFound = false;

      function getVar(iframeIndex, varName) {
        return window.frames[iframeIndex].window[varName];
      }

      function output(name, txt) {
        el = document.getElementById(`output${name}`);
        el.innerHTML += `${txt}<br />`;
      }

      function checkSecurityError() {
        // https://stackoverflow.com/questions/25893006/uncaught-securityerror-blocked-a-frame-with-origin-null-from-accessing-a-fram
        try {
          window.frames[0].window.Date();
        } catch(e) {
          if (!securityErrorFound) { alert(`Error: ${e.message}`); };
          securityErrorFound = true;
          throw e;
        }
      }

      function iframeOnload(name, index) {
        checkSecurityError();
        output(name, `<strong>myDate instanceof Date</strong>: ${getVar(index, 'myDate') instanceof Date}`)
        output(name, `<strong>myString instanceof String</strong>: ${getVar(index, 'myString') instanceof String}`)
      }
    </script>
  </head>
  <body>
    <h1 style="margin-bottom:0">Frame boundaries</h1>
    <h3 style="margin-top:0;color:#555;font-weight:normal">Proof of concept</h3>

    <table border="1">
      <tr>
        <th>context</th>
        <th>
          iframe A
          <br />(<a href="a.html" target="_blank">a.html</a>)
        </th>
        <th>
          iframe B
          <br />(<a href="b.html" target="_blank">b.html</a>)
        </th>
      </tr>
      <tr>
        <td>inside of iframe</td>
        <td><iframe src="a.html" onload="iframeOnload('A', 0)" frameborder="0" style="height:110px"></iframe></td>
        <td><iframe src="b.html" onload="iframeOnload('B', 1)" frameborder="0" style="height:110px"></iframe></td>
      </tr>
      <tr>
        <td>outside of iframe</td>
        <td><div id="outputA" style="margin:8px"></div></td>
        <td><div id="outputB" style="margin:8px"></div></td>
      </tr>
    </table>

    <br />

    <a href="https://stackoverflow.com/questions/643782/how-to-check-whether-an-object-is-a-date#comment38499658_643827" target="_blank">
      Reference
    </a>
  </body>
</html>
	<!doctype html>
	<html lang="en">
	<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title>iframe A</title>
	<script>
	window.myDate = new Date();
	window.myString = new String('A');
	</script>
	</head>
	<body bgcolor="#e5edff">
	myDate = <span id="var1"></span><br />
	<strong>instanceof Date is <span id="val1"></span></strong>
	<hr />
	myString: <span id="var2"></span><br />
	<strong>instanceof String is <span id="val2"></span></strong>

	<script>
	window.myDate = new Date();
	document.getElementById('var1').innerText = window.myDate.toISOString();
	document.getElementById('val1').innerText = window.myDate instanceof Date;

	document.getElementById('var2').innerText = window.myString;
	document.getElementById('val2').innerText = window.myString instanceof String;
	</script>
	</body>
	</html>
	<!doctype html>
	<html lang="pt-bt">
	<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title>Proof of concept: Frame boundaries</title>

	<script>
	var securityErrorFound = false;

	function getVar(iframeIndex, varName) {
	return window.frames[iframeIndex].window[varName];
	}

	function output(name, txt) {
	el = document.getElementById(`output${name}`);
	el.innerHTML += `${txt}<br />`;
	}

	function checkSecurityError() {
	// https://stackoverflow.com/questions/25893006/uncaught-securityerror-blocked-a-frame-with-origin-null-from-accessing-a-fram
	try {
	window.frames[0].window.Date();
	} catch(e) {
	if (!securityErrorFound) { alert(`Error: ${e.message}`); };
	securityErrorFound = true;
	throw e;
	}
	}

	function iframeOnload(name, index) {
	checkSecurityError();
	output(name, `<strong>myDate instanceof Date</strong>: ${getVar(index, 'myDate') instanceof Date}`)
	output(name, `<strong>myString instanceof String</strong>: ${getVar(index, 'myString') instanceof String}`)
	}
	</script>
	</head>
	<body>
	<h1 style="margin-bottom:0">Frame boundaries</h1>
	<h3 style="margin-top:0;color:#555;font-weight:normal">Proof of concept</h3>

	<table border="1">
	<tr>
	<th>context</th>
	<th>
	iframe A
	<br />(<a href="a.html" target="_blank">a.html</a>)
	</th>
	<th>
	iframe B
	<br />(<a href="b.html" target="_blank">b.html</a>)
	</th>
	</tr>
	<tr>
	<td>inside of iframe</td>
	<td><iframe src="a.html" onload="iframeOnload('A', 0)" frameborder="0" style="height:110px"></iframe></td>
	<td><iframe src="b.html" onload="iframeOnload('B', 1)" frameborder="0" style="height:110px"></iframe></td>
	</tr>
	<tr>
	<td>outside of iframe</td>
	<td><div id="outputA" style="margin:8px"></div></td>
	<td><div id="outputB" style="margin:8px"></div></td>
	</tr>
	</table>

	<br />

	<a href="https://stackoverflow.com/questions/643782/how-to-check-whether-an-object-is-a-date#comment38499658_643827" target="_blank">
	Reference
	</a>
	</body>
	</html>