You can pass jQuery more than one selector expression
You can provide the jQuery function's first parameter several expressions separated by a
comma: $('expression, expression, expression'). In other words, you are not limited to
selecting elements using only a single expression. For example, in the example below, I am
passing the jQuery function three expressions separated by a comma.
Sample: sample24.html
jQuery
is the
best!
Each of these expressions selects DOM elements that are all added to the wrapper set. We can
then operate on these elements using jQuery methods. Keep in mind that all the selected
elements will be placed in the same wrapper set. An inefficient way to do this would be to call
the jQuery function three times, once for each expression.
Checking wrapper set .length to determine selection
It is possible to determine if your expression has selected anything by checking if the wrapper
set has a length. You can do so by using the array property length. If the length property does
not return 0, then you know at least one element matches the expression you passed to the
jQuery function. For example, in the code below we check the page for an element with an id of
"notHere." Guess what? It is not there!
Sample: sample25.html
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