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In JavaScript can I make a “click” event fire programmatically for a file input element?
...u cannot do that in all browsers, supposedly IE does allow it, but Mozilla and Opera do not.
When you compose a message in GMail, the 'attach files' feature is implemented one way for IE and any browser that supports this, and then implemented another way for Firefox and those browsers that do not...
Is there an auto increment in sqlite?
... you should try to avoid:
INSERT INTO people VALUES ("John", "Smith");
and use
INSERT INTO people (first_name, last_name) VALUES ("John", "Smith");
instead. The first version is very fragile — if you ever add, move, or delete columns in your table definition the INSERT will either fail o...
How do you know when to use fold-left and when to use fold-right?
I'm aware that fold-left produces left-leaning trees and fold-right produces right-leaning trees, but when I reach for a fold, I sometimes find myself getting bogged down in headache-inducing thought trying to determine which kind of fold is appropriate. I usually end up unwinding the entire proble...
Rails: Using build with a has_one association in rails
...
The build method signature is different for has_one and has_many associations.
class User < ActiveRecord::Base
has_one :profile
has_many :messages
end
The build syntax for has_many association:
user.messages.build
The build syntax for has_one association:
user.bu...
Cannot find module cv2 when using OpenCV
...
First do run these commands inside Terminal/CMD:
conda update anaconda-navigator
conda update navigator-updater
Then the issue for the instruction below will be resolved
For windows if you have anaconda installed, you can simply do
pip install...
What is the optimal algorithm for the game 2048?
...directions to make "bigger" tiles. After each move, a new tile appears at random empty position with a value of either 2 or 4 . The game terminates when all the boxes are filled and there are no moves that can merge tiles, or you create a tile with a value of 2048 .
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Hidden Features of PHP? [closed]
... language - everything else I have to piece together from various websites and man pages.
share
edited Feb 23 '10 at 20:28
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Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
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Why is using “for…in” for array iteration a bad idea?
...5;
for (var x in a) {
// Shows only the explicitly set index of "5", and ignores 0-4
console.log(x);
}
/* Will display:
5
*/
Also consider that JavaScript libraries might do things like this, which will affect any array you create:
// Somewhere deep in your JavaScript...
How to open a web server port on EC2 instance
...to the "Network & Security" -> Security Group settings in the left hand navigation
Find the Security Group that your instance is apart of
Click on Inbound Rules
Use the drop down and add HTTP (port 80)
Click Apply and enjoy
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