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How to check if a variable is not null?
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They are not equivalent. The first will execute the block following the if statement if myVar is truthy (i.e. evaluates to true in a conditional), while the second will execute the block if myVar is any value other than null.
The only values that are not truthy in JavaScript are the following (a...
Get path of executable
...os.html to select the method is straightforward.
– Clifford
Oct 7 '09 at 15:02
5
So is this what ...
Checking if jquery is loaded using Javascript
I am attempting to check if my Jquery Library is loaded onto my HTML page. I am checking to see if it works, but something is not right. Here is what I have:
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jquery if div id has children
This if -condition is what's giving me trouble:
7 Answers
7
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jQuery.inArray(), how to use it right?
...ay returns the index of the element in the array, not a boolean indicating if the item exists in the array. If the element was not found, -1 will be returned.
So, to check if an item is in the array, use:
if(jQuery.inArray("test", myarray) !== -1)
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How to find if a given key exists in a C++ std::map
I'm trying to check if a given key is in a map and somewhat can't do it:
14 Answers
14...
How to check if an array value exists?
How can I check if $something['say'] has the value of 'bla' or 'omg' ?
12 Answers
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How to convert a Hibernate proxy to a real entity object
...using.
public static <T> T initializeAndUnproxy(T entity) {
if (entity == null) {
throw new
NullPointerException("Entity passed for initialization is null");
}
Hibernate.initialize(entity);
if (entity instanceof HibernateProxy) {
entity = (T) (...
xpath find if node exists
Using a xpath query how do you find if a node (tag) exists at all?
6 Answers
6
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How to check if function exists in JavaScript?
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Try something like this:
if (typeof me.onChange !== "undefined") {
// safe to use the function
}
or better yet (as per UpTheCreek upvoted comment)
if (typeof me.onChange === "function") {
// safe to use the function
}
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