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Unit 8: Programming Constructs in JavaScript




          An optional radix parameter can also be used to specify the number system to be used to parse  Notes
          the string argument. For example,
          document.write(parseInt(“10”,16));

          Result:
          16
          16 is the radix value passed, which means the string should be converted from hexadecimal to
          decimal value. If the radix is 8, then the string should be converted from octal to decimal value.
          If the radix parameter is not specified, then Javascript
              Assumes radix to be 16(hexadecimal), if the string starts with “0x”
              Assumes radix to be 8(octal), if the string starts with 0

              Assumes radix to be 10(decimal), if the string starts with any other number.
          parseFloat()
          parseFloat() function takes a string as parameter and parses it to a floating point number.
          document.write(parseFloat(“10.33”));

          document.write(parseFloat(“15 66 75”));
          document.write(parseFloat(“this is 77”));
          document.write(pareFloat(“ 77 “));
          Result:

          10.33
          15
          NaN
          77

          This function allows leading and trailing spaces. If  the first character in the string  is not  a
          number, then  it returns NaN. If the string has more  than one  set of  number separated  by
          delimiters such as spaces, semicolons,commas then it returns only the first set of number before
          the first delimiter.
          escape()

          escape() function encodes the string passed to it so that it can be used across any network, say for
          example in query strings.
          document.write(escape(“testing escape function!!”));

          Result:
          testing%20escape%20function%21%21
          escape() function leaves digits, latin letters and the characters + - * / . _ @ unchanged and replaces
          all other characters with ASCII code of the original character preceded by % symbol.

               !
             Caution  The radix can be any number ranging from 2 to  36 that represents a numeral
             system.




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