Example of initial values of Boolean objects in js

A Boolean (logical) object is used to convert non-logical values to logical values (true or false ).
Create a Boolean object

Use the keyword new to define a Boolean object. The following code defines a logical object named myBoolean:

Var myBoolean = new Boolean ()

Note: If the logical object has no initial value or its value is 0,-0, null, "", false, undefined, Or NaN, the object value is false. Otherwise, the value is true (even when the independent variable is string "false )!

All the following code lines will create a Boolean object whose initial value is false.
Copy codeThe Code is as follows:
<Script type = "text/javascript">
Var myBoolean = new Boolean ();
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean (0 );
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean (null );
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean ("");
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean (false );
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean (NaN );
Document. write (myBoolean );
Document. write ("<br/> ");
</Script>

Running result:

False
False
False
False
False
False

All the following code lines will create a Boolean object whose initial value is true:
Copy codeThe Code is as follows:
<Script type = "text/javascript">
Var myBoolean = new Boolean (1 );
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean (true );
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean ("true ");
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean ("false ");
Document. write (myBoolean );
Document. write ("<br/> ");

Var myBoolean = new Boolean ("Bill Gates ");
Document. write (myBoolean );
Document. write ("<br/> ");
</Script>

Running result:

True
True
True
True
True
This initial value is different from that of java and c. You should pay attention to it later!