string.LastIndexOf()

info

Hi guys. I don't know if it is only me,or what,but simple function from class String - LastIndexOf() works for me well only if there is only first attribute assigned and nothing else. If I try write something like this : string strS = "abcdefghijkl"; int a = strS.LastIndexOf("c",0,5); it always throw exception : Count must be positive and count must refer to a location within the string/array/collection. Does it happend to You too or is just something wrong with me ? Thanks. Rodenpro

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info21y ago
Thank you very much. Hmm..realy not intuitive at all !!. Thanks.Appreciate. Rodenpro.
ytram521y ago
Ok, figured it out. The LastIndexOf method will scan backward, not forwards, so it is essentially asking for a backwards substring. Using your example: strS = "abcdefghijkl"; int a = strS.LastIndexOf("c",0,5) //will throw an exception int b = strS.LastIndexOf("c",6,5) //This will examine the substring "cdefg" for the string "c". It's not as intuitive as IndexOf's overload similar to this. Here is the URL where I got this information: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemstringclasslastindexoftopic6.asp
ytram521y ago
I am testing this, and getting the same exception. It's extremely odd, as count shouldn't refer to a location, it is the number of characters to scan.