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Is there a performance impact when calling ToList()?
...) does have a performance impact, it is an O(n) operation though it will likely only require attention in performance critical operations.
The ToList() operation will use the List(IEnumerable<T> collection) constructor. This constructor must make a copy of the array (more generally IEnumerabl...
How to get rid of blank pages in PDF exported from SSRS
I have a two-page SSRS report. When I exported it to PDF it was taking 4 pages due to its width, where the 2nd and 4th pages were displaying one of my fields from the table. I tried to set the layout size in report properties as width=18in and height =8.5in.
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OR is not supported with CASE Statement in SQL Server
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OMG PoniesOMG Ponies
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How do I get the current time only in JavaScript
How can I get the current time in JavaScript and use it in a timepicker?
18 Answers
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Windows XP or later Windows: How can I run a batch file in the background with no window displayed?
I know I have already answered a similar question ( Running Batch File in background when windows boots up ), but this time I need to launch a batch:
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Setting the filter to an OpenFileDialog to allow the typical image formats?
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Sebastian Brosch
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answered Jan 15 '10 at 2:37
itowlsonitowlson
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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...ted (e.g. hashes and strings), not just arrays.
TL;DR: Use Hash.new { |h, k| h[k] = [] } if you want the most idiomatic solution and don’t care why.
What doesn’t work
Why Hash.new([]) doesn’t work
Let’s look more in-depth at why Hash.new([]) doesn’t work:
h = Hash.new([])
h[0] <&...
Simplest way to detect a mobile device in PHP
...AGENT'];
if(preg_match('/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap...
How to count the number of files in a directory using Python
...ntity), use os.path.isfile():
import os, os.path
# simple version for working with CWD
print len([name for name in os.listdir('.') if os.path.isfile(name)])
# path joining version for other paths
DIR = '/tmp'
print len([name for name in os.listdir(DIR) if os.path.isfile(os.path.join(DIR, name))])...
Keyboard shortcut to paste clipboard content into command prompt window (Win XP) [closed]
Is there a keyboard shortcut for pasting the content of the clipboard into a command prompt window on Windows XP (instead of using the right mouse button)?
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