| 5. 2. 1. Boolean |
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The Boolean object is a wrapper object that holds a primitive Boolean value. |
The Boolean object provides a method for converting the value to a string. |
A primitive boolean can have only one of two states: true or false. |
JavaScript uses the number 1 to represent true and 0 to represent false but provides the toString() method to return the strings "true" and "false". |
A Boolean object is created with the Boolean() constructor and the new operator or by the Boolean() function. |
Constructor: |
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var variable = new Boolean(value)
var variable = Boolean(value)
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value is the value to be converted to a Boolean value and stored in the object. |
The values null, NaN, "" (empty string), and 0 (zero) are converted to false. |
All other values (including the string "false") are converted to true. |
If the new operator is used, the new Boolean object is returned. |
If the Boolean() function is used, the primitive Boolean value is returned. |
Method toString() returns a string representation of the primitive Boolean value. |
If the object contains true, the string "true" is returned. |
If the object contains false, the string "false" is returned. |
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<HTML>
<BODY>
<SCRIPT language="JavaScript">
<!--
var myVariable=false;
document.write(myVariable);
//-->
</SCRIPT>
</BODY>
</HTML>
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