拥有真正值的一切均为 true
- <!DOCTYPE html>
- <html>
- <body>
- <p id="demo"></p>
- <script>
- var b1 = Boolean(100);
- var b2 = Boolean(3.14);
- var b3 = Boolean(-15);
- var b4 = Boolean("Hello");
- var b5 = Boolean('false');
- var b6 = Boolean(1 + 7 + 3.14);
- document.getElementById("demo").innerHTML =
- "100 是 " + b1 + "<br>" +
- "3.14 是 " + b2 + "<br>" +
- "-15 是 " + b3 + "<br>" +
- "任何(非空)字符串是 " + b4 + "<br>" +
- "即使字符串 'false' 也是 " + b5 + "<br>" +
- "任何表达式(除了零)是 " + b6;
- </script>
- </body>
- </html>