Operating with substrings in strings

[Heinz]

Hi, i haven't found a function in the phobos lib to read a block of chars of a
given length from a string taking the start index as a parameter, for example:
we have the word "hello", i want to read starting from index 1 and i want this
substring to have a length of 2, so the result should be "el", i've seen this
in other languages, the function looks like: GetSubString(string mystring, int
startindex, int length).

Is there a way to acomplish this?

Thx