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by Scott Hanselman.
Original Post: The Daily Brain Fart - LastIndexOf broken? Oh, no, 'tis me.
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Often, in the scope of writing massively scalable enterprise systems that manage your
finances, I parse strings. Mostly in my spare time.
What's happening here? I was reminded today that the start index passed to LastIndexOf()
was from the ass-end of the string. I then lamented the obviousness of this and was
then humbled by the silent-but-deadly odor my own brain fart.
I'm glad you're that much more confident in my abilities after reading this post.
Up with TDD! Down with ADD!
publicstaticvoid Main()
{ int newlineIndex = -1; string x ="bob\neric\nfred\nted"; string z ="bob\r\neric\r\nfred\r\nted";
newlineIndex = x.LastIndexOf('\n',0);
Console.WriteLine(newlineIndex); //Expect
13, always get -1
newlineIndex = z.LastIndexOf('\n',0);
Console.WriteLine(newlineIndex); //Expect
16, always get -1
newlineIndex = x.LastIndexOf('\n');
Console.WriteLine(newlineIndex); //Expect
13, get 13
newlineIndex = z.LastIndexOf('\n');
Console.WriteLine(newlineIndex); //Expect
16, get 16
//Fart
realized...
newlineIndex = x.LastIndexOf('\n',x.Length-1);
Console.WriteLine(newlineIndex); //Expect
13, always get 13
newlineIndex = z.LastIndexOf('\n',z.Length-1);
Console.WriteLine(newlineIndex); //Expect
13, always get 13
}
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