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Will ConfigurationManager.AppSettings[“blah”] throw an exception if “blah” doesn't exist?
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From the MSDN documentation for NameValueCollection.Item Property (String):
Caution
This property returns null in the following cases: 1) if the specified key is not found; and 2) if the specified key is found and its associ...
Passing arguments to an interactive program non-interactively
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Many ways
pipe your input
echo "yes
no
maybe" | your_program
redirect from a file
your_program < answers.txt
use a here document (this can be very readable)
your_program << ANSWERS
yes
no
maybe
ANSWERS
use a here string
your_program <<< $'yes\nno\nmaybe\n'
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How to convert char to int?
...'0' which is then the 'base value'
subtracting your number in char format from this will give you the original number.
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How to display Base64 images in HTML?
...rking. You may try specifying char set.
<div>
<p>Taken from wikpedia</p>
<img src="data:image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAAUA
AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot" />
</di...
Entity Framework - Start Over - Undo/Rollback All Migrations
...If you want to run enable-migrations again and you are developing database from scratch you just need to follow the last sentence: delete database and all migration related code. If you started using migrations with existing database you first have to revert all migrations by using the second or thi...
Why does ++[[]][+[]]+[+[]] return the string “10”?
...e over +):
++[[]][0]
+
[0]
Because [[]][0] means: get the first element from [[]], it is true that:
[[]][0] returns the inner array ([]). Due to references it's wrong to say [[]][0] === [], but let's call the inner array A to avoid the wrong notation.
++ before its operand means “increment by...
Using comparison operators in Scala's pattern matching system
...ke such an assumption without some risk of the implementation changing out from underneath.
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Rename Files and Directories (Add Prefix)
... the paramerter-replacing option of xargs: -I. And you can get more detail from the man page.
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How to check if a map contains a key in Go?
...:
initializes two variables - val will receive either the value of "foo" from the map or a "zero value" (in this case the empty string) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" i...
How do I write data into CSV format as string (not file)?
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since i use this quite a lot to stream results asynchronously from sanic back to the user as csv data i wrote the following snippet for Python 3.
The snippet lets you reuse the same StringIo buffer over and over again.
import csv
from io import StringIO
class ArgsToCsv:
def __i...