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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...
How do I check how many options there are in a dropdown menu?
...
var length = $('#mySelectList').children('option').length;
or
var length = $('#mySelectList > option').length;
This assumes your <select> list has an ID of mySelectList.
http://api.jquery.com/length/
http://api.jquery.com/childr...
Select where count of one field is greater than one
...clause, for aggregate result comparison.
Taking the query at face value:
SELECT *
FROM db.table
HAVING COUNT(someField) > 1
Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY...
Is this in preparati...
Check if value is in select list with JQuery
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Use the Attribute Equals Selector
var thevalue = 'foo';
var exists = 0 != $('#select-box option[value='+thevalue+']').length;
If the option's value was set via Javascript, that will not work. In this case we can do the following:
var exists = fal...
SQL Server: Examples of PIVOTing String data
...l as numbers. This query will only require the table to be scanned once.
SELECT Action,
MAX( CASE data WHEN 'View' THEN data ELSE '' END ) ViewCol,
MAX( CASE data WHEN 'Edit' THEN data ELSE '' END ) EditCol
FROM t
GROUP BY Action
...
MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
...
Clear form field after select for jQuery UI Autocomplete
I'm developing a form, and using jQuery UI Autocomplete. When the user selects an option, I want the selection to pop into a span appended to the parent <p> tag. Then I want the field to clear rather than be populated with the selection.
...
How to change the href for a hyperlink using jQuery
...l hyperlinks to point to Google. You probably want a somewhat more refined selector though. For instance, if you have a mix of link source (hyperlink) and link target (a.k.a. "anchor") anchor tags:
<a name="MyLinks"></a>
<a href="http://www.codeproject.com/">The CodeProject</a&...
T-SQL: Selecting rows to delete via joins
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DELETE FROM TableA a WHERE [filter condition on TableA]
AND (a.BId IN (SELECT a.BId FROM TableB b JOIN TableA a
ON a.BId = b.BId
WHERE [filter condition on TableB]))
(Note Interbase doesn't support the AS keyword for aliases)
...
How to get all options of a select using jQuery?
How can I get all the options of a select through jQuery by passing on its ID?
17 Answers
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