从网上找了很多关于placeholder IE兼容性的问题，下边的这个js方法可以显示password。
<!doctype html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Placeholder Polyfill Test</title> </head> <body> <form> <input type="password"placeholder="password"> <input type="password"placeholder="confirm password"> </form> <script src="http://code.jquery.com/jquery-1.10.0.min.js"></script> <script> /* placeholder polyfill plugin */ /*! http://mths.be/placeholder v2.0.7 by @mathias */ (function(f, h, $) { var a='placeholder'in h.createElement('input'), d='placeholder'in h.createElement('textarea'), i=$.fn, c=$.valHooks, k, j; if(a&&d) { j=i.placeholder=function() { return this } ; j.input=j.textarea=true } else { j=i.placeholder=function() { var l=this; l.filter((a?'textarea':':input')+'[placeholder]').not('.placeholder').bind( { 'focus.placeholder':b, 'blur.placeholder':e } ).data('placeholder-enabled', true).trigger('blur.placeholder'); return l } ; j.input=a; j.textarea=d; k= { get:function(m) { var l=$(m); return l.data('placeholder-enabled')&&l.hasClass('placeholder')?'':m.value } , set:function(m, n) { var l=$(m); if(!l.data('placeholder-enabled')) { return m.value=n } if(n=='') { m.value=n; if(m!=h.activeElement) { e.call(m) } } else { if(l.hasClass('placeholder')) { b.call(m, true, n)||(m.value=n) } else { m.value=n } } return l } } ; a||(c.input=k); d||(c.textarea=k); $(function() { $(h).delegate('form', 'submit.placeholder', function() { var l=$('.placeholder', this).each(b); setTimeout(function() { l.each(e) } , 10) } ) } ); $(f).bind('beforeunload.placeholder', function() { $('.placeholder').each(function() { this.value='' } ) } ) } function g(m) { var l= { } , n=/^jQueryd+$/; $.each(m.attributes, function(p, o) { if(o.specified&&!n.test(o.name)) { l[o.name]=o.value } } ); return l } function b(m, n) { var l=this, o=$(l); if(l.value==o.attr('placeholder')&&o.hasClass('placeholder')) { if(o.data('placeholder-password')) { o=o.hide().next().show().attr('id', o.removeAttr('id').data('placeholder-id')); if(m===true) { return o[0].value=n } o.focus() } else { l.value=''; o.removeClass('placeholder'); l==h.activeElement&&l.select() } } } function e() { var q, l=this, p=$(l), m=p, o=this.id; if(l.value=='') { if(l.type=='password') { if(!p.data('placeholder-textinput')) { try { q=p.clone().attr( { type: 'text' } ) } catch(n) { q=$('<input>').attr($.extend(g(this) { type: 'text' } )) } q.removeAttr('name').data( { 'placeholder-password':true, 'placeholder-id':o } ).bind('focus.placeholder', b); p.data( { 'placeholder-textinput':q, 'placeholder-id':o } ).before(q) } p=p.removeAttr('id').hide().prev().attr('id', o).show() } p.addClass('placeholder'); p[0].value=p.attr('placeholder') } else { p.removeClass('placeholder') } } } (this, document, jQuery)); </script> <script> $('input').placeholder(); </script> </body> </html>
转自这里 http://zach.lysobey.com/files/placeholder/index.html