js提交form表单 - input file 文件上传控制上传文件的大小和格式

js提交form表单

所以我总结了一下，用Javascript提交表单大概有两种写法（根据我目前的理解）

1. document.formName.submit();

2. var form = document.getElementById(id);

form.submit();

input file 文件上传控制上传文件的大小和格式

html

<form  action="/ask/addaskrecordattachment2" enctype="multipart/form-data" method="post" id="attachment_uploads">
<div class="attachs fl">
<div class="t_fjfont">附件:</div>
<div class="upload_btns"><input type="file" name="file"  id="file" onchange="fileChange(this);" /> <input type="hidden" name="id" class="hideids" /></div>
<div class="upload_btns" style="color:red;" id="upsizelabel"> (为了保证您的询价质量及服务，请先下载材料模板)</div>
</div>
<div class="attachs fl">
<div class="t_fjfont" style="color:red;font-size:12px;font-weight:bold">文件上限2MB</div>
<div class="upload_btns" style="color:0066CC;text-decoration: underline;"> <a href="javascript:getDownload();" >附件表格样式（下载）</a></div>
</div>
<div class="attachs fl">
<div class="t_fjfont"> </div>
<div class="upload_btns"><input type="file" name="files"  id="file_fujian" onchange="filefujianChange(this);" /> <input type="hidden" name="rev" class="hide_rev" /></div>
<div class="upload_btns" style="color:red;" id="upsizelabel"> (请上传CAD图纸或者图片格式，此处不接受询价单)</div>
</div>
<div class="clear"></div>
</form>

js

function fileChange(target) {
var fileSize = 0;
if (isIE && !target.files) {
var filePath = target.value;
var fileSystem = new ActiveXObject("Scripting.FileSystemObject");
var file = fileSystem.GetFile (filePath);
fileSize = file.Size;
} else {
fileSize = target.files[0].size;
}
var size = fileSize / 1024;
if(size>2000){
alert("附件不能大于2M");
target.value="";
return
}
var name=target.value;
var fileName = name.substring(name.lastIndexOf(".")+1).toLowerCase();
if(fileName !="xls" && fileName !="xlsx"){
alert("请选择execl格式文件上传！");
target.value="";
return
}
}

function filefujianChange(target) {
var fileSize = 0;
if (isIE && !target.files) {
var filePath = target.value;
var fileSystem = new ActiveXObject("Scripting.FileSystemObject");
var file = fileSystem.GetFile (filePath);
fileSize = file.Size;
} else {
fileSize = target.files[0].size;
}
var size = fileSize / 1024;
if(size>2000){
alert("附件不能大于2M");
target.value="";
return
}
var name=target.value;
var fileName = name.substring(name.lastIndexOf(".")+1).toLowerCase();
if(fileName !="jpg" && fileName !="jpeg" && fileName !="pdf" && fileName !="png" && fileName !="dwg" && fileName !="gif" ){
alert("请选择图片格式文件上传(jpg,png,gif,dwg,pdf,gif等)！");
target.value="";
return
}
}

ps:支持市面上主流的浏览器~~~~~IE，谷歌，FF都支持！