大约有 46,000 项符合查询结果（耗时：0.0473秒） [XML]
Reference: Comparing PHP's print and echo
...e should one wish to use print in a conditional expression. Why 1 and not 100? Well in PHP the truthiness of 1 or 100 is the same, i.e. true, whereas 0 in a boolean context equates as a false value. In PHP all non-zero values (positive and negative) are truthy values and this derives from PHP's Per...
Assigning a variable NaN in python without numpy
...
170
Yes -- use math.nan.
>>> from math import nan
>>> print(nan)
nan
>>>...
How to detect current state within directive
...
darthwadedarthwade
1,42411 gold badge1010 silver badges55 bronze badges
add a comment
...
How can I change Mac OS's default Java VM returned from /usr/libexec/java_home
...efaults to picking the newest JDK from /Library/Java as long as that is 7u10 or later, or uses Java 6 if your Java 7 installation is update 9 or earlier. But unravelling the logic in the shell scripts it looks to me like you can specify a particular JDK using a configuration file.
Create a text fi...
What does the `#` operator mean in Scala?
...t; val a1 = new A
a1: A = A@1497b7b1
scala> val a2 = new A
a2: A = A@2607c28c
scala> a2.f(new a1.B)
<console>:11: error: type mismatch;
found : a1.B
required: a2.B
a2.f(new a1.B)
^
scala> a2.g(new a1.B)
Got a B.
...
Can jQuery get all CSS styles associated with an element?
...r (var i in css) {
var l = css[i].split(": ");
s[l[0].toLowerCase()] = (l[1]);
}
}
return s;
}
Pass a jQuery object into css() and it will return an object, which you can then plug back into jQuery's $().css(), ex:
var style = css($("#elementToGetAllCSS"));...
Check image width and height before upload with Javascript
...file").change(function (e) {
var file, img;
if ((file = this.files[0])) {
img = new Image();
var objectUrl = _URL.createObjectURL(file);
img.onload = function () {
alert(this.width + " " + this.height);
_URL.revokeObjectURL(objectUrl);
...
Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
...
answered Feb 15 '12 at 0:25
Dan WichDan Wich
4,74311 gold badge2222 silver badges2222 bronze badges
...
How to count TRUE values in a logical vector
...
answered Feb 3 '10 at 12:29
MarekMarek
43.9k1313 gold badges8484 silver badges114114 bronze badges
...
Is it safe to remove selected keys from map within a range loop?
... one iteration to the next. If the map is nil, the number of iterations is 0.
share
|
improve this answer
|
follow
|
...