无刷新上传解析csv文件
前阵子工作中用到，贴上代码，仅保留上传有关的代码，发现code其实很少。
上传页面html/js
<!
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
>
处理文件上传的c#code
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>
"
);
}
做到无刷新，基本原理就是：通过表单提交到iframe里，从而使刷新发生在iframe里。form设置action指向处理上传的文件，target指向iframe。上传操作的结果可以返回到iframe里，调用父对象的FinishUpload方法显示是否上传成功。所以在AJAX未流行时，常用这种方法来伪装未刷新的效果，现在仍然可以使用。
要注意的是：
- enctype="multipart/form-data"不可少，enctype默认编码是“application/x-www-form-urlencoded”，设置enctype="multipart/form-data"，用于二进制方式上传文件。
- 为防止文件名乱码，防止乱七八糟字符URL传递中出现问题，返回文件名到前台时进行HttpUtility.UrlEncode，在前台JS中取文件名时进行decodeURIComponent。
- 重置文件选择框时，要把文件选择框临时插入到临时表单，通过表单的reset方法重置。
顺便贴上解析上传的csv文件的code
解析csv文件
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);
}