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Method/                      Description                                    Example
                 Property
               search        It returns the position of the first match, -1 otherwise.  text = "I am studying JavaScript";
                                                                          document.write(text.search("studying"))
                                                                          Output:5
                                                                          document.write(text.search("Math"))
                                                                          Output: -1


                 4.19 TYPE CONVERSIONS IN JAVASCRIPT

              When two distinct types of data are used in an expression, JavaScript automatically converts the data and evaluates
              the expression. This action is called type conversion. In JavaScript, there are two ways to convert the type:


                                                            Type Conversion




                                        Implicit Type Conversion           Explicit Type Conversion


              Implicit Type Conversion
              When an expression is evaluated and two different types are given that are incompatible to perform the operation,
              JavaScript automatically converts them. The following are some examples of implicit conversions:

              Ð ÐIf one value is a number and the other is a string, the expression turns the string to a number and performs the
                 arithmetic operation. For example, 12 * “5” returns the number 60, and 2 – “5” returns -3.

              Ð ÐIn arithmetic operations, if a value is null, it is converted to the integer value 0. The outcome of null + 8 is 8, for
                 example.

              Ð ÐIn an arithmetic operation, if one value is Boolean, it is converted to 0 or 1 depending on the provided value. True
                 + 6 yields a result of 7, while false+8 yields a value of 8.

              Ð ÐIf the value cannot be translated to another type, it is returned as NaN (Not a Number).
              Explicit Type Conversion

              The developer does this type of conversion by utilizing the built-in type conversion methods. The various methods to
              explicitly convert data are as follows:

                    Method                               Description                                 Example
               Number( )         Converts any value to number. NaN is returned if the value cannot be  Number(false)
                                 converted.                                                 Output:0
                                                                                            Number(“77”)
                                                                                            Output:77
                                                                                            Number(“69 58”)
                                                                                            Output:NaN
               parseInt( )       This  method  accepts  two  arguments  and  returns  an  integer  value.  parseInt(“30 years”)
                                 Syntax: parseInt(string, radix)                            Output: 30
                                 string—The value that has to be parsed (required)          parseInt(“20.43”)
                                 radix—The  default  value  is  10.  The  number  system  is  specified  by  Output: 20
                                 numbers 2–36. (Optional)                                   parseInt(“He is 30 years”)
                                                                                            Output: NaN
                                                                                            parseInt(“20”, 8)
                                                                                            Output: 16

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