大约有 35,406 项符合查询结果（耗时：0.0416秒） [XML]
Determining whether jQuery has not found any element
...t').length is what you're looking for. (If it finds nothing, this will === 0.) So your conditional statement should probably be:
if($('#id').length) { /* code if found */ } else { /* code if not found */ }
You're getting an object returned from that alert because jQuery (almost) always returns the...
What is AssemblyInfo.cs used for?
...tab of the file properties you will see no name,
no description, version 0.0.0.0, etc.
The value associated with assembly:Guid is the ID that will identify
the assembly if it will be exposed as a COM object. So, if your
assembly isn't COM-exposed, you don't need this. It is randomly
gen...
Is there any way to ignore INSTALL_FAILED_VERSION_DOWNGRADE on application install with the Android
...
290
It appears the latest version of adb tools has an "allow downgrade flag" that isn't shown in the...
How to pad zeroes to a string?
...
2506
Strings:
>>> n = '4'
>>> print(n.zfill(3))
004
And for numbers:
>>&...
What does |= (ior) do in Python?
...
Here we apply merge (|) and update (|=) to dicts:
>>> d1 = {"a": 0, "b": 1, "c": 2}
>>> d2 = {"c": 20, "d": 30}
>>> # Merge, |
>>> d1 | d2
{"a": 0, "b": 1, "c": 20, "d": 30}
>>> d1
{"a": 0, "b": 1, "c": 2}
>>> # Update, |=
>>> d1 |=...
How to create json by JavaScript for loop?
...ID"); // this works too
var status = document.getElementsByName("status")[0];
var jsonArr = [];
for (var i = 0; i < status.options.length; i++) {
jsonArr.push({
id: status.options[i].text,
optionValue: status.options[i].value
});
}
</script>
...
How to see top processes sorted by actual memory usage?
...dsarnold
94.7k1919 gold badges157157 silver badges210210 bronze badges
...
How to test multiple variables against a value?
...
+500
You misunderstand how boolean expressions work; they don't work like an English sentence and guess that you are talking about the sam...
Javascript swap array elements
... = list[y];
list[y] = list[x];
list[x] = b;
Edit hijacking top answer 10 years later with a lot of ES6 adoption under our belts:
Given the array arr = [1,2,3,4], you can swap values in one line now like so:
[arr[0], arr[1]] = [arr[1], arr[0]];
This would produce the array [2,1,3,4]. This is ...
How to unstash only certain files?
...e git checkout or git show to restore a specific file.
git checkout stash@{0} -- <filename>
With Git 2.23+ (August 2019), use git restore, which replaces the confusing git checkout command:
git restore -s stash@{0} -- <filename>
That does overwrite filename: make sure you didn't have l...