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How to repeat a string a variable number of times in C++?
...ng in C++. Is there any direct way to do this using either std::strings or char* strings?
8 Answers
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How to bind inverse boolean properties in WPF?
... which is easily missed when it (as is often the case) is embedded next to chars that look like it (i.e. one/more "("'s and "l"'s and "I"'s).
– Tom
Jan 18 '18 at 1:54
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Get query string parameters url values with jQuery / Javascript (querystring)
... = key.replace(/[*+?^$.\[\]{}()|\\\/]/g, "\\$&"); // escape RegEx meta chars
var match = location.search.match(new RegExp("[?&]"+key+"=([^&]+)(&|$)"));
return match && decodeURIComponent(match[1].replace(/\+/g, " "));
}
http://jsfiddle.net/gilly3/sgxcL/
An alternat...
typecast string to integer - Postgres
...ur value is an empty string, you can use NULLIF to replace it for a NULL:
SELECT
NULLIF(your_value, '')::int
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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...dn't want the overhead of a function. I came up with the following query:
SELECT myfield::integer FROM mytable WHERE myfield ~ E'^\\d+$';
Postgres shortcuts its conditionals, so you shouldn't get any non-integers hitting your ::integer cast. It also handles NULL values (they won't match the regex...
What's the difference between KeyDown and KeyPress in .NET?
...ctical difference between KeyDown and KeyPress is that KeyPress relays the character resulting from a keypress, and is only called if there is one.
In other words, if you press A on your keyboard, you'll get this sequence of events:
KeyDown: KeyCode=Keys.A, KeyData=Keys.A, Modifiers=Keys.None
Key...
Adding 'serial' to existing column in Postgres
...int, b text);
CREATE TABLE bar (a serial, b text);
INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;
-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER...
Trigger change event of dropdown
...wns, the best way to do it is to have a script that returns the a prebuilt select box and an AJAX call that requests it.
Here is the documentation for jQuery's Ajax method if you need it.
$(document).ready(function(){
$('#countrylist').change(function(e){
$this = $(e.target);
...
MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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Emacs on Mac OS X Leopard key bindings
...
⌘ + → - move to end of current line
Shift + any of the above extend selection by appropriate amount
Click then drag - select text
Double-click then drag - select text, wrapping to word ends
Triple-click then drag - select text, wrapping to paragraph ends
Shift + Select text with mouse - add...