用js实现预览待上传的本地图片

<form name=”form5′′ id=”form5′′ method=”post” action=”#”> <input type=”file” name=”file5′′ id=”file5′′ onchange=”preview5()”/> </form> [removed] function preview5(){ var x = document.getElementById(“file5”); if(!x || !x.value) return; var patn = /\.jpg$|\.jpeg$|\.gif$/i; if(patn.t