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How to get the first five character of a String
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You can use Enumerable.Take like:
char[] array = yourStringVariable.Take(5).ToArray();
Or you can use String.Substring.
string str = yourStringVariable.Substring(0,5);
Remember that String.Substring could throw an exception in case o...
Django: Get an object form the DB, or 'None' if nothing matches
Is there any Django function which will let me get an object form the database, or None if nothing matches?
8 Answers
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Position geom_text on dodged barplot
...1) instead of position = "dodge", which is just a shortcut without any parameter.
In ggplot2_2.0.0 you find several examples in ?geom_text on how to position geom_text on dodged or stacked bars (the code chunk named "# Aligning labels and bars"). The Q&A What is the width argument in positi...
How to convert JSON data into a Python object
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UPDATE
With Python3, you can do it in one line, using SimpleNamespace and object_hook:
import json
from types import SimpleNamespace
data = '{"name": "John Smith", "hometown": {"name": "New York", "id": 123}}'
# Parse JSON into an object with attributes corresponding to dict keys.
x =...
How to set date format in HTML date input tag?
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You don't.
Firstly, your question is ambiguous - do you mean the format in which it is displayed to the user, or the format in which it is transmitted to the web server?
If you mean the format in which it is displayed to the user, then this is down to the end-user interface, not ...
Test whether string is a valid integer
I'm trying to do something common enough: Parse user input in a shell script. If the user provided a valid integer, the script does one thing, and if not valid, it does something else. Trouble is, I haven't found an easy (and reasonably elegant) way of doing this - I don't want to have to pick it ap...
How can I make an entire HTML form “readonly”?
...he first page has a submission form, and the second page has an acknowledgement form. The first form offers a choice of many controls, while the second page displays the data from the submission form again with a confirmation message. On this second form all fields must be static.
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setting an environment variable in virtualenv
I have a Heroku project that uses environment variables to get its configuration, but I use virtualenv to test my app locally first.
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Python timedelta in years
I need to check if some number of years have been since some date. Currently I've got timedelta from datetime module and I don't know how to convert it to years.
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How to format a JavaScript date
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For custom-delimited date formats, you have to pull out the date (or time)
components from a DateTimeFormat object (which is part of the
ECMAScript Internationalization API), and then manually create a string
with the delimiters you want.
To do this, you can use DateTimeFormat#formatToParts. You...