大约有 36,010 项符合查询结果（耗时：0.0515秒） [XML]
Count the number of occurrences of a string in a VARCHAR field?
...
This should do the trick:
SELECT
title,
description,
ROUND (
(
LENGTH(description)
- LENGTH( REPLACE ( description, "value", "") )
) / LENGTH("value")
) AS count ...
Detecting an “invalid date” Date instance in JavaScript
...
Here's how I would do it:
if (Object.prototype.toString.call(d) === "[object Date]") {
// it is a date
if (isNaN(d.getTime())) { // d.valueOf() could also work
// date is not valid
} else {
// date is valid
}
} else {
// not...
Select2 dropdown but allow new values by user?
I want to have a dropdown with a set of values but also allow the user to "select" a new value not listed there.
9 Answers...
Image comparison - fast algorithm
... the hardest to implement.
Keypoint Matching
Better than picking 100 random points is picking 100 important points. Certain parts of an image have more information than others (particularly at edges and corners), and these are the ones you'll want to use for smart image matching. Google "keypoi...
Why Does OAuth v2 Have Both Access and Refresh Tokens?
...n is compromised, because it is short-lived, the attacker has a limited window in which to abuse it.
Refresh tokens, if compromised, are useless because the attacker requires the client id and secret in addition to the refresh token in order to gain an access token.
Having said that, because every...
SQlite Getting nearest locations (with latitude and longitude)
...*/
public static PointF calculateDerivedPosition(PointF point,
double range, double bearing)
{
double EarthRadius = 6371000; // m
double latA = Math.toRadians(point.x);
double lonA = Math.toRadians(point.y);
double angularDistance = range / EarthRadiu...
Max or Default?
... to get the Max value from a LINQ query that may return no rows? If I just do
17 Answers
...
Compiling/Executing a C# Source File in Command Prompt
How do you compile and execute a .cs file from a command-prompt window?
15 Answers
15
...
How to check if IEnumerable is null or empty?
...e<T> (or IQueryable<T>, although that's a different scenario). Doing so consumes the sequence, at least partially (although that still means it is consumed) - it might only need to read one element (especially if there is no predicate). As such, since sequences (IEnumerable<T>) do ...
try {} without catch {} possible in JavaScript?
... case those functions should not throw errors but return e.g. null and you do something like return func1() || func2() || func3();
– ThiefMaster
Apr 23 '11 at 13:08
53
...