Asp.Net多附件上传

时间:2022-08-28 19:28:24

对于asp.net程序,我们应该尽可能的提供一个便捷的用户接口,减少页面回传就是其中之一。

本文演示一次上传多个文件的方法,在客户端可以随意控制上传文件的个数,但是注意总文件大小不能过大,否则会有异常抛出。至于解决大文件上传的方法已经超出本文的讨论范围。

这里有一个要点大家不要忽略了,否则程序不能正常工作。
就是必须指定form的enctype="multipart/form-data" 属性

代码如下:

<%@ Page language="c#" Codebehind="MultiAttchments.aspx.cs" AutoEventWireup="false" Inherits="WebApplication3.MultiAttchments" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
      <HEAD>
            <script>
            function AddAttachments()
            {
                  document.getElementById('attach').innerText = "继续添加附件";
                 
                  tb = document.getElementById('attAchments');                 
                  newRow = tb.insertRow();
                  newRow.insertCell().innerHTML = "<input name='File' size='50' type='file'>&nbsp;&nbsp;<input type=button value='删除' onclick='delFile(this.parentElement.parentElement.rowIndex)'>";
            }
            function delFile(index)
            {
                  document.getElementById('attAchments').deleteRow(index);
                  tb.rows.length > 0?document.getElementById('attach').innerText = "继续添加附件":document.getElementById('attach').innerText = "添加附件";
            }
            </script>
      </HEAD>
      <body MS_POSITIONING="GridLayout">
            <form id="form1" method="post" runat="server" enctype="multipart/form-data">
            <div><table id="attAchments"></table></div><span><IMG src="icoAddFl.gif"> </span> <A id="attach" style="font-family:宋体;font-size:9pt;" title="如果您要发送多个附件,您只需多次点击“继续添加附件”即可, 要注意附件总量不能超过发送限制的大小。" onclick="AddAttachments();"
                        href="javascript:;" name="attach">添加附件</A>
                  <br><br><br><br><br><br>
                  <asp:Button id="btnSend" runat="server" Text=" 上传 "></asp:Button>
            </form>
      </body>
</HTML>

private void btnSend_Click(object sender, System.EventArgs e)
{
      StringBuilder sb = new StringBuilder();

 

      int attCount = 0;
      string filePath = "";
            for(int i=0; i< Request.Files.Count; i++)
            {
                  if(Request.Files[i].ContentLength > 0)
                  {
                        filePath = Request.Files[i].FileName;
                        sb.Append("Files" + attCount++ + ": " + filePath + "<br>");
                        Request.Files[0].SaveAs(Server.MapPath("./") + filePath.Substring(filePath.LastIndexOf("\\")+1));
                  }
            }

      sb.Insert(0, "you upload " + attCount + " files.<br>");
      Response.Write(sb.ToString());
}



完整源码下载