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CS0120: An object reference is required for the nonstatic field, method, or property 'foo'
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For this case, where you want to get a Control of a Form and are receiving this error, then I have a little bypass for you.
Go to your Program.cs and change
Application.Run(new Form1());
to
public static Form1 form1 = new Form1(); // Place this var out of the constructor
Appli...
How does JavaScript .prototype work?
...e code you write. The square brackets around [[Prototype]] are deliberate, and are an ECMAScript specification convention to denote internal slots.
The value pointed at by the [[Prototype]] of an object, is colloquially known as "the prototype of that object."
If you access a property via the do...
How to read a single char from the console in Java (as the user types it)?
...t you want to do is put the console into "raw" mode (line editing bypassed and no enter key required) as opposed to "cooked" mode (line editing with enter key required.) On UNIX systems, the 'stty' command can change modes.
Now, with respect to Java... see Non blocking console input in Python and ...
Rails select helper - Default selected value, how?
...g to edit your record.
You need to set the default to your existing value and then only set it to the actual default if you don't have a value. Like so:
f.select :field, options_for_select(value_array, f.object.field || default_value)
For anyone not familiar with f.object.field you always use f....
Python None comparison: should I use “is” or ==?
...n comparing arbitrary objects to singletons like None because it is faster and more predictable. is always compares by object identity, whereas what == will do depends on the exact type of the operands and even on their ordering.
This recommendation is supported by PEP 8, which explicitly states th...
How do you concatenate Lists in C#?
...working fine I think so. As previously said, Concat returns a new sequence and while converting the result to List, it does the job perfectly.
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Converting a Java collection into a Scala collection
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JavaConversions (robinst's answer) and JavaConverters (Ben James's answer) have been deprecated with Scala 2.10.
Instead of JavaConversions use:
import scala.collection.convert.wrapAll._
as suggested by aleksandr_hramcov.
Instead of JavaConverters use:
i...
Plotting time in Python with Matplotlib
I have an array of timestamps in the format (HH:MM:SS.mmmmmm) and another array of floating point numbers, each corresponding to a value in the timestamp array.
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Why must a lambda expression be cast when supplied as a plain Delegate parameter
... new delegate type with an appropriate signature, but that's rarely useful and you end up with less opportunity for error checking.
If you want to make it easy to call Control.Invoke with an Action the easiest thing to do is add an extension method to Control:
public static void Invoke(this Contro...
What do the different readystates in XMLHttpRequest mean, and how can I use them?
XMLHttpRequest has 5 readyState s, and I only use 1 of them (the last one, 4 ).
5 Answers
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