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P. 351

Method                               Description                                  Example

                 parseFloat( )     The parseFloat() method returns the first decimal number after parsing  parseFloat(“20.45”)
                                   a value as a string. NaN is returned if the initial character cannot be  Output: 20.45
                                   converted.                                                 parseFloat(“44 56”)
                                                                                              Output:44
                 eval( )           A JavaScript expression is passed as a string argument to this method.  eval(“5*4”)
                                   After that, eval( ) evaluates the expression and returns the result. It  Output: 20
                                   returns undefined if no result is received.
                 String            A value is converted to a string.                          String(false)
                                                                                              Output: false
                                                                                              String(Boolean(1))
                                                                                              Output: true String(“65”)
                                                                                              Output: 65
                 Boolean           Checks if an expression is true.                           Boolean(20 > 7)
                                                                                              Output: true
                                                                                              X=null; Boolean(X)
                                                                                              Output: false

                 Example:

                   <!DOCTYPE html>

                   <HTML>
                   <BODY>
                   <H1>JavaScript Global Methods</H1>

                   <H2>The eval() Method</H2>
                   <SCRIPT>
                   let x = 10;

                   let y = 20;
                   let text = "x * y";
                   let result = eval(text);

                   document.write(result);
                   </SCRIPT>

                   </BODY>
                   </HTML>
                 Output of the above code is as follows:



















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