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Today, I will talk to you about how jquery determines whether an element has an attribute. Many people may not know much about it. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

In jquery, you can use the attr () method to determine whether an element has an attribute, the syntax "$(selector) .attr (attrName)"; if there is an attrName attribute, it returns the value of attrName, and if it does not, it returns "undefined".

The operating environment of this tutorial: windows7 system, jquery1.10.2 version, Dell G3 computer.

In jquery, you can use the attr () method to determine whether an element has an attribute.

The attr () method returns the attribute value of the selected element, syntax:

$(selector) .attr (attrName)

If there is an attrName property, it returns the value of attrName, and if it does not exist, it returns "undefined" (undefined is the undefined type).

So to use attributes when judging, you can judge based on the results:

If (typeof ($(selector) .attr (attrName)) = = "undefined") {console.log ("attribute does not exist");} else {console.log ("attribute exists");} after reading the above, do you have any further understanding of how jquery determines whether an element has an attribute? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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