Determination steps: 1. Use children() to obtain all direct subset elements of the specified element. The syntax "specified element object.children();" will return a jquery object containing subset elements; 2. Use the length attribute to count jquery objects. The number of elements in the subset, the syntax is "jquery object.length"; 3. Use the ">=" operator to determine whether the number of elements in the subset is greater than or equal to 1, the syntax is "number of elements >= 1", if it is greater than or equal to If 1, there are sub-elements, otherwise there are no sub-elements.
The operating environment of this tutorial: windows7 system, jquery3.6.0 version, Dell G3 computer.
jquery method to determine whether an element has child elements
In jquery, you can use the children() method and length attribute to determine whether an element has child elements.
Implementation steps:
Step 1: Use children() to get all direct subset elements of the specified element
Specify element object.children();will return a jquery object containing the subset elements
Step 2: Use the length attribute to count the number of subset elements in the jquery object
jquery object.lengthStep 3: Use the ">=" operator to determine whether the number of subset elements is greater than or equal to 1
The number of subset elements >= 1If greater than or equal to 1, there are child elements in the specified element.
If less than 1, there are child elements in the specified element
Implementation code:
<!DOCTYPE html><html><head><meta charset="utf-8"><script src="js/jquery-3.6.0.min.js"></script><script type="text/ javascript">$(document).ready(function() {$("button").click(function() {$len=$("div").children().length;if ($len>=1 ) {console.log("There are child elements in the specified element");} else {console.log("There are no child elements in the specified element");}});});</script></head><body ><div style="border: 1px solid red;"><p>Child element 1</p><span>Child element 2</span><span>Child element 2</span><p>Child element 3 </p><p>Child element 4</p></div><br><button>Specify whether the div element has child elements</button></body></html>
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