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Web Programming




                    Notes             split
                                      substr
                                      subString
                                   Now let’s see one by one what can we do with them and how to use them in a JavaScript code.

                                   length

                                   Syntax:  object.length;
                                   This function returns with the total number of characters in the string, or more simple it returns
                                   with the length of the string. The usage is quite simple:
                                   Code:
                                         var  str  =  ‘Demo  text.’;
                                   var  len  =  str.length;
                                   var  len2  =  ‘my  other  text’.length;
                                   toLowerCase  and  toUpperCase
                                   Synatx:  object.toLowerCase();
                                   These methods can be very useful if you want to all character in a string lower case or upper case.
                                   For example if you want to compare 2 strings but you are not sure if they are capitalized or not.
                                   In this case just convert both of them to lower or upper case and you can make the comparison
                                   without any problem.


                                          Example: Usage example:
                                   Code:
                                   var  str  =  ‘Demo  Text.’;
                                   var  strL  =  str.toLowerCase();
                                   var  strU  =  str.toUpperCase();
                                   if  (str.toLowerCase()  ==  ‘demo  text.’)

                                   charAt

                                   Synatx: object.charAt(index);
                                   With this function you can get the character at the given position in a string. If you want you can
                                   read the complete string character by character using charAt and a loop.

                                          Example: See the examples:

                                   Code:
                                   var  str  =  ‘Demo  Text.’;
                                   var  c      =  str.charAt(5);
                                   for  (i=0;i<str.length;i++){
                                   alert(str.charAt(i));
                                      }





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