1 　　　　　　if(FileUpload1.PostedFile.ContentLength ==0)
2 {
3 stringstr =@"The file name is invalid or the file is empty. A file name can not contain any of the following characters: \ / : * ? "" < > | # { } % ~ & ";
4 labMsg.Text =str;
5 labMsg.Visible =true;
6 return;
7 }
8 if(FileUpload1.PostedFile !=null)
9 {
10 //Check upload file extension name
11 stringfileExtension =System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();
12 if(fileExtension ==string.Empty ||fileExtension ==null)
13 {
14 stringstr =@"The file is not extension name.";
15 labMsg.Text =str;
16 labMsg.Visible =true;
17 return;
18 }
19 else
20 {
21 labMsg.Visible =false;
22 }
23 stringfileName =FileUpload1.FileName;
24 intindex =fileName.LastIndexOf(".");
25 fileName =fileName.Substring(0, index);
26 List<string>characters =newList<string>();//\ / : * ? " < > | # { } % ~ & //特殊字符不只有这些，
27 charc ='"';
28 characters.Add("\\");
29 characters.Add("/");
30 characters.Add(":");
31 characters.Add("*");
32 characters.Add("?");
33 characters.Add(c.ToString());
34 characters.Add("<");
35 characters.Add(">");
36 characters.Add("|");
37 characters.Add("#");
38 characters.Add("{");
39 characters.Add("}");
40 characters.Add("%");
41 characters.Add("~");
42 characters.Add("&");
43 foreach(stringstr incharacters)
44 {
45 if(fileName.Contains(str))
46 {
47 stringmessage =@"The file name is invalid or the file is empty. A file name can not contain any of the following characters: \ / : * ? "" < > | # { } % ~ & .";
48 labMsg.Text =message;
49 labMsg.Visible =true;
50 return;
51 }
52 }
53
54 if(CSP.Infrastructure.CSPUtility.CheckUploadFileType(fileExtension.Substring(1)))
55 {
56 stringmessage =@"The following file(s) have been blocked by the administrator: "+FileUpload1.FileName;
57 labMsg.Text =message;
58 labMsg.Visible =true;
59 return;
60 }
61
62 if(FileUpload1.PostedFile.ContentLength >52100000)
63 {
64 labMsg.Text ="Can not upload file that the file size lager 50 M.";
65 labMsg.Visible =true;
66 return;
67 }
68 else
69 {
70 labMsg.Visible =false;
71 }
72
73 if(ViewState["Attachment"] ==null)
74 {
75 ViewState["Attachment"] =CreateDtAttachment();
76 }
77 DataTable dt =(DataTable)ViewState["Attachment"];
78 stringname =FileUpload1.FileName.Trim();
79 DataRow[] rows =dt.Select("AttachmentName = '"+name +"'");
80 if(rows.Length >0)
81 {
82 //Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "msg", "<script>alert('" + FileUpload1.FileName + " is exist !');</script>");
83 labMsg.Text =FileUpload1.FileName +"already exists.";
84 labMsg.Visible =true;
85 return;
86 }
87 else
88 {
89 labMsg.Visible =false;
90 }
91 DataRow row =dt.NewRow();
92 if(dt.Rows.Count !=null)
93 {
94 row["AttachmentId"] =(dt.Rows.Count +1).ToString();
95 }
96 else
97 {
98 row["AttachmentId"] ="0";
99 }
100
101 row["AttachmentName"] =FileUpload1.FileName;
102
103 intlen =FileUpload1.FileBytes.Length;
104 byte[] fileContent =newbyte[len];
105 FileUpload1.FileContent.Read(fileContent, 0, len);
106
107 row["AttachContent"] =fileContent;
108 dt.Rows.Add(row);
109 ViewState["Attachment"] =dt;
110 GvDataBind();
111 }

其实还有一些其他特殊字符也会报出此错误。
 

在上传文件的时候需要取得管理中心，限制上传文件的类型，这样就可以与管理中心允许上传文件的列表保持一致，代码如下：

http://www.cnblogs.com/dexter2003/archive/2010/12/05/1887806.html