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Check if option is selected with jQuery, if not select a default
Using jQuery, how do you check if there is an option selected in a select menu, and if not, assign one of the options as selected.
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&& (AND) and || (OR) in IF statements
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No, it will not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other way around
if (str == null || str.isEmpty()) {
com...
How to check if a map contains a key in Go?
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One line answer:
if val, ok := dict["foo"]; ok {
//do something here
}
Explanation:
if statements in Go can include both a condition and an initialization statement. The example above uses both:
initializes two variables - val will r...
Simple C example of doing an HTTP POST and consuming the response
...sage body separated by a blank line. The blank line is ALWAYS needed even if there is no message body. The header starts with a command and has additional lines of key value pairs separated by a colon and a space. If there is a message body, it can be anything you want it to be.
Lines in the hea...
JavaScript is in array
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Try this:
if(blockedTile.indexOf("118") != -1)
{
// element found
}
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follo...
Placeholder in IE9
...h ie9 the placeholder disappears when the text input is on focus. This is different than HTML5 behavior
– gerrytan
Apr 8 '14 at 1:35
1
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What is the simplest and most robust way to get the user's current location on Android?
...Some may be disabled on the device, some may be disabled in application manifest.
If any provider is available I start location listeners and timeout timer. It's 20 seconds in my example, may not be enough for GPS so you can enlarge it.
If I get update from location listener I use the provided value...
How to check if a json key exists?
So, I get some JSON values from the server but I don't know if there will be a particular field or not.
13 Answers
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Why is it considered a bad practice to omit curly braces? [closed]
...t's ever really bit me was when I was debugging, and commented out bar():
if(foo)
// bar();
doSomethingElse();
Other than that, I tend to use:
if(foo) bar();
Which takes care of the above case.
EDIT Thanks for clarifying the question, I agree, we should not write code to the lowest common d...
jQuery: Test if checkbox is NOT checked
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One reliable way I use is:
if($("#checkSurfaceEnvironment-1").prop('checked') == true){
//do something
}
If you want to iterate over checked elements use the parent element
$("#parentId").find("checkbox").each(function(){
if ($(this).prop('c...