asp.net+js 實現無重新整理上傳解析csv檔案的代碼

最後更新：2018-12-08 來源：互聯網

上載者：User

創建阿里雲帳戶，並獲得超過 40 款產品的免費試用版；而企業帳戶則可以享有總值 $1200 的免費試用版。立即註冊！

前陣子工作中用到，貼上代碼，僅保留上傳有關的代碼，發現code其實很少。
上傳頁面html/js 複製代碼代碼如下:<!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></title>
<script type="text/javascript">
function FinishUpload(filePath) {
document.getElementById("uploadForm").reset();
if (!filePath) {
alert("Import Failed!");
}
else {
alert("Imported Successfully to " + decodeURIComponent(filePath) + "!");
}
}
function UploadFile() {
var arr = document.getElementById("txtFile").value.split('.');
var fileType = arr[arr.length - 1];
if (fileType.toLowerCase().indexOf("csv") < 0) {
document.getElementById("uploadForm").reset();
alert("Please select a csv file.");
return false;
}
document.getElementById("uploadForm").encoding = "multipart/form-data";
document.getElementById("uploadForm").submit();
}
function ResetFile(file) {
var tmpForm = document.createElement('form');
file.parentNode.insertBefore(tmpForm, file);
tmpForm.appendChild(file);
tmpForm.reset();
tmpForm.removeNode(false);
}
</script>
</head>
<body>
<form id="uploadForm" name="uploadForm" action="Upload.ashx" method="post" target="hidIframe" enctype="multipart/form-data">
<table cellpadding='0' cellspacing='0' style="width:100%;height:100%;border-collapse:collapse;" border="0" >
<tr>
<td>
<input id="txtFile" name="txtFile" type="file" style="border:solid 1px Gray;" />
<iframe name="hidIframe" id="hidIframe" style="display:none;" ></iframe>
</td>
</tr>
<tr>
<td>
<input type="button" id="btnImportOK" value="Upload" onclick="UploadFile();" />
<input type="button" id="btnImportCancel" onclick="ResetFile(document.getElementById('txtFile'))" value="Reset"/>
</td>
</tr>
</table>
</form>
</body>
</html>

　
處理檔案上傳的c# 複製代碼代碼如下:if (context.Request.Files.Count > 0)
{
HttpPostedFile file = context.Request.Files[0];
if (file.ContentLength > 0)
{
string title = string.Empty;
title = DateTime.Now.ToString("yyyyMMddHHmmss") + "_" + Path.GetFileName(file.FileName);
string path = "./Upload/" + title;
path = System.Web.HttpContext.Current.Server.MapPath(path);
file.SaveAs(path);
context.Response.Write("<script>window.parent.FinishUpload('" + HttpUtility.UrlEncode(path) + "');</script>");
}
}
else
{
context.Response.Write("<script>window.parent.FinishUpload('');</script>");
}

　　做到無重新整理，基本原理就是：通過表單提交到iframe裡，從而使重新整理發生在iframe裡。form設定action指向處理上傳的檔案，target指向iframe。上傳操作的結果可以返回到iframe裡，調用父物件的FinishUpload方法顯示是否上傳成功。所以在AJAX未流行時，常用這種方法來偽裝未重新整理的效果，現在仍然可以使用。
要注意的是：
enctype="multipart/form-data"不可少，enctype預設編碼是“application/x-www-form-urlencoded”，設定enctype="multipart/form-data"，用於二進位方式上傳檔案。
為防止檔案名稱亂碼，防止亂七八糟字元URL傳遞中出現問題，返迴文件名到前台時進行HttpUtility.UrlEncode，在前台JS中取檔案名稱時進行decodeURIComponent。
重設檔案選擇框時，要把檔案選擇框臨時插入到暫存資料表單，通過表單的reset方法重設。
順便貼上解析上傳的csv檔案的code
解析csv檔案複製代碼代碼如下:private DataTable ImportDataTable(string filepath)
{
DataTable mydt = new DataTable("myTableName");
mydt.Columns.Add("Data ID", System.Type.GetType("System.String"));
mydt.Columns.Add("Field Name", System.Type.GetType("System.String"));
mydt.Columns.Add("New Value", System.Type.GetType("System.String"));
DataRow mydr;
using (System.IO.StreamReader mysr = new System.IO.StreamReader(filepath))
{
int data;
char current;
StringBuilder text = new StringBuilder();
IDictionary<int, List<string>> results = new Dictionary<int, List<string>>();
bool isInYinHao = false; ;
int lineId = 1;
int index = 0;
while (true)
{
data = mysr.Read();
if (data != -1)
{
current = (char)data;
if (current == '"')
{
if (isInYinHao)
{
isInYinHao = false;
}
else
{
if (index > 0)
{
text.Append(current);
}
isInYinHao = true;
}
}
else if (current == ',')
{
if (isInYinHao)
{
text.Append(current);
}
else
{
SaveResult(results, lineId, text);
index = 0;
continue;
}
}
else if (current == '\r')
{
if (isInYinHao)
{
text.Append(current);
}
}
else if (current == '\n')
{
if (isInYinHao)
{
text.Append(current);
}
else
{
SaveResult(results, lineId, text);
index = 0;
lineId++;
continue;
}
}
else if (current == '\0')
{
}
else
{
text.Append(current);
}
index++;
}
else
{
//Read to file end.
SaveResult(results, lineId, text);
break;
}
}
foreach (int id in results.Keys)
{
mydr = mydt.NewRow();
for (int i = 0; i < results[id].Count; i++)
{
if (i > 2)
{
break;
}
mydr[i] = results[id][i];
}
mydt.Rows.Add(mydr);
}
}
return mydt;
}
private void SaveResult(IDictionary<int, List<string>> results, int lineId, StringBuilder text)
{
if (!results.ContainsKey(lineId))
{
results.Add(lineId, new List<string>());
}
results[lineId].Add(text.ToString());
text.Remove(0, text.Length);
}

點擊下載

本文章原先以中文撰寫並發佈於 aliyun.com，亦設英文版本，僅作資訊用途。本網站不對文章的準確性，完整性或可靠性或其任何翻譯作出任何明示或暗示的陳述或保證。如對該文章有任何疑慮或投訴，請傳送電郵至 info-contact@alibabacloud.com 並提供相關疑慮或投訴的詳細說明。職員會於 5 個工作天內與您聯絡，一經驗證之後，即會刪除該侵權內容。

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

Get Started for Free

Sales Support

1 on 1 presale consultation

Chat Contact Sales
After-Sales Support

24/7 Technical Support 6 Free Tickets per Quarter Faster Response

Open a Ticket
Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.

Learn More