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jQuery selector symbol analysis

小云云

Nov 28, 2017 am 10:11 AM

jqueryanalyzeSelector

jQuery is a cross-browser JavaScript library that simplifies operations between HTML and JavaScript. We often use it during programming development, so in this chapter we will briefly introduce to you the meaning of some symbols in jQuery selectors.

Space: $('#phpernote span')

means to get all span nodes and all descendants under id=phpernote.

Greater than sign: $('#phpernote > span')

means to obtain all the first-level span nodes with id=phpernote, that is, the first generation, and will not be obtained for other generations.

Plus sign: $('#phpernote + .com')

means to obtain the next class=com sibling node of the id=phpernote node, which is equivalent to the next() method.

Tilde sign: $('#phpernote ~ span')

means to obtain all span sibling nodes behind the node with id=phpernote, which is equivalent to the nextAll() method.

The above is the symbol analysis in several jQuery selectors, I hope it can help everyone.

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