The Substr method returns a substring of the specified length starting at the specified position. Stringvar.substr (start [, length]) parameter stringvar required option. The string literal or string object to extract the substring from. Start Required option. The starting position of the desired substring. The index of the first character in the string is 0. Length can be selected. The number of characters that should be included in the returned substring. Description if length is 0 or negative, an empty string is returned. If this argument is not specified, the substring continues to the end of the stringvar. Example The following example demonstrates the use of the Substr method. function Substrdemo () {var s, SS; Declares a variable. var s = "The rain in Spain falls mainly in the plain."; SS = S.substr (12, 5); Gets a substring. return (SS); Returns "Spain". The}substring method returns a substring that is located at the specified position in a string object. Strvariable.substring (Start, end) "String Literal". The substring (start, end) parameter start indicates the starting position of the substring starting at 0. End indicates the ending position of the substring, starting at 0. Description The Substring method returns a string containing a substring from start to last (without end). The substring method uses the smaller values from start and end as the starting point for the substring. For example, strvar.substring (0, 3) and strvar.substring (3, 0) will return the same substring. If start or end is NaN or negative, replace it with 0. The length of the substring equals the absolute value of the difference between start and end. For example, the length of the substring returned in strvar.substring (0, 3) and strvar.substring (3, 0) is 3. Example The following example demonstrates the use of the substring method. function Substringdemo () {var ss; Declares a variable. var s = "The rain in Spain falls mainly in the plain."; SS = S.substring (12, 17); Takes a substring. return (SS); Returns a substring. }
Intercept strings substr and substring, but don't.