<!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> <title> new document </title> <meta charset="UTF-8"> <meta name="generator" content="editplus" /> <meta name="author" content="" /> <meta name="keywords" content="" /> <meta name="description" content="" /> <script src="jquery.min.js"></script> <script> function check() { var objFile = document.getElementById("fileId"); if(objFile.value == "") { alert("不能空") } console.log(objFile.files[0].size); // 文件字节数 var files = $('#fileId').prop('files');//获取到文件列表 if(files.length == 0){ alert('请选择文件'); }else{ var reader = new FileReader();//新建一个FileReader reader.readAsText(files[0], "UTF-8");//读取文件 reader.onload = function(evt){ //读取完文件之后会回来这里 var fileString = evt.target.result; // 读取文件内容 alert(fileString); } } } </script> </head> <body> <div> 上传文件 ： <input type="file" name = "file" id = "fileId" /> <button type = "submit" name = "btn" value = "提交" id = "btnId" onclick="check()" /> 提交 </div> </body> </html>