Kongsi contoh cara jQuery menyembunyikan dan memaparkan nilai lalai input.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>jQuery 隐藏与显示 input 默认值</title> <script language="javascript" src="jquery-1.7.1.min.js"></script> </head> <body> <p><input type="text" value="请输入邮箱地址" id="email" id="email" /></p> <p><input type="button" value="提交" /></p> <script type="text/javascript"> $("#email").focus(function(){ var email_txt = $(this).val(); if (email_txt == this.defaultValue) { $(this).val(""); } }) $("#email").blur(function(){ var email_txt = $(this).val(); if (email_txt == "") { $(this).val(this.defaultValue); } }) </script> </body> </html>