Three methods for jQuery to determine whether the checkbox is selected

The check box selection status of forms is often judged in projects, and the following three common methods are summarized:

Method 1 (recommended):

 if($("#checkbox").is(":checked")) {     // do something }

Method 2:

 if ($("#checkbox").attr("checked")) {     // do something }

Method 3:

 if ($("#checkbox").get(0).checked) {     // do something }