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asked by Expert (15k points) 15 23 31 | 59 views

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<!DOCTYPE HTML>
<html>
<body>
  <script type="text/javascript">
    var myData = {
      name : "JavaScript",
      city : null
    };
    if (!myData.name) {
      document.writeln("name IS null or undefined");
    } else {
      document.writeln("name is NOT null or undefined");
    }
    if (!myData.city) {
      document.writeln("city IS null or undefined");
    } else {
      document.writeln("city is NOT null or undefined");
    }
  </script>
</body>
</html>
If a variable or property is null or undefined, the coerced boolean value is false.
 
 
answered by Advisor (8.4k points) 10 15 18

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