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Find an item in List by LINQ?
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If you want the index of the element, this will do it:
int index = list.Select((item, i) => new { Item = item, Index = i })
.First(x => x.Item == search).Index;
// or
var tagged = list.Select((item, i) => new { Item = item, Index = i });
int index = (from pair in tagged
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The new keyword “auto”; When should it be used to declare a variable type? [duplicate]
...e individual octets of the address (e.g., representing each as an unsigned char), so we end up with something like octets[0] & mask[0]. Thanks to C's type promotion rules, even if both operands are unsigned chars, the result is typically going to be int. We need the result to be an unsigned char...
Rails raw SQL example
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You can do this:
sql = "Select * from ... your sql query here"
records_array = ActiveRecord::Base.connection.execute(sql)
records_array would then be the result of your sql query in an array which you can iterate through.
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In Python, when to use a Dictionary, List or Set?
...om a sequence, and computing mathematical operations such as intersection, union, difference, and symmetric difference.
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Extract month and year from a zoo::yearmon object
...an extract the date parts as required:
> format(date1, "%b") ## Month, char, abbreviated
[1] "Mar"
> format(date1, "%Y") ## Year with century
[1] "2012"
> format(date1, "%m") ## numeric month
[1] "03"
These are returned as characters. Where appropriate, wrap in as.numeric() if you want t...
Common MySQL fields and their appropriate data types
... that is either an ID or references another ID
DATETIME for time stamps
VARCHAR(255) for anything guaranteed to be under 255 characters (page titles, names, etc)
TEXT for pretty much everything else.
Of course there are exceptions, but I find that covers most eventualities.
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Algorithm to return all combinations of k elements from n
... takes an array of letters as an argument and a number of those letters to select.
71 Answers
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__FILE__ macro shows full path
...lity tool would be careful to split file names at both slash and backslash characters to avoid any problems for folks that do manage to use /.
– RBerteig
Sep 13 '12 at 20:53
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Multiple file upload in php
... what would the expected outcome be? Browser allowing multiple files to be selected?
– Sven
Oct 3 '12 at 17:41
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What does the unary plus operator do?
... answered Oct 11 '10 at 2:07
Charles SalviaCharles Salvia
47.1k1212 gold badges116116 silver badges137137 bronze badges
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