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Restricting input to textbox: allowing only numbers and decimal point
How can I restrict input to a text-box so that it accepts only numbers and the decimal point?
32 Answers
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How to flatten tree via LINQ?
...er style", convert Flatten to a generic extension method that takes a tree and a function that produces descendants from a node:
public static IEnumerable<T> Flatten<T>(
this IEnumerable<T> e
, Func<T,IEnumerable<T>> f
) => e.SelectMany(c => f(c).Flatten(f)...
What is the difference between Gemfile and Gemfile.lock in Ruby on Rails
I am a beginner to Ruby on Rails and I am using Rails 3.0.9.
3 Answers
3
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How do I replace text in a selection?
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This frustrated the heck out of me, and none of the above answers really got me what I wanted. I finally found the answer I was looking for, on a mac if you do ⌘ + option + F it will bring up a Find-Replace bar at the bottom of your editor which is local to t...
What RSA key length should I use for my SSL certificates?
I'm in the process of creating a CSR, and I wonder which is arguably the best length for my RSA key.
8 Answers
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How to resize a VirtualBox vmdk file
I've run out of space on a virtual machine disk which is a vmdk and need to resize the virtual image. Resizing with the command
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Panel.Dock Fill ignoring other Panel.Dock setting
If you create a panel on a form and set it to Dock=Top and drop another panel and set its Dock=Fill, it may fill the entire form, ignoring the first panel. Changing the tab order does nothing.
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SQL how to make null values come last when sorting ascending
...e with a datetime field. The field in question can be null. I have a query and I want the results sorted ascendingly by the datetime field, however I want rows where the datetime field is null at the end of the list, not at the beginning.
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Rails extending ActiveRecord::Base
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Create a file in the config/initializers directory called extensions.rb and add the following line to the file:
require "active_record_extension"
Inheritance (Preferred)
Refer to Toby's answer.
Monkey patching (Should be avoided)
Create a file in the config/initializers directory called act...
What does “error: option --single-version-externally-managed not recognized” indicate?
...not recognized when pip install ing varions packages (including PyObjC and astropy ). I've never seen this error before, but it's now also showing up on travis-ci builds for which nothing has changed.
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