[TOC] ## .one - 处理函数在每个元素上每种事件类型最多执行一次 - 原理为处理后使用off删除绑定 ``` $("#foo").one("click", function() { alert("This will be displayed only once."); }); ``` 等效于 ``` $( "#foo" ).on( "click", function( event ) { alert( "This will be displayed only once." ); $( this ).off( event ); }); ``` ### 语法 ``` .one( events [, data ], handler(eventObject) ) .one( events [, selector ] [, data ], handler(eventObject) ) .one( events [, selector ] [, data ] ) ``` ### 示例 ``` $("#foo").one("click", function() { alert("This will be displayed only once."); }); ```