1. #region 将二进制转化为文件  
2.         public static string ConvertByteToFile(object objData, string filePathName)  
3.         {  
4.             //string fileName = "";              
5.             //fileName = new PublicConst().PathTempFile + fileName;  
6.             string folder = System.IO.Path.GetDirectoryName(filePathName);  
7.             if (!System.IO.Directory.Exists(folder))  
8.             {  
9.                 System.IO.Directory.CreateDirectory(folder);  
10.             }  
11.             if (System.IO.File.Exists(filePathName))  
12.             {  
13.                 try  
14.                 {  
15.                     System.IO.File.Delete(filePathName);  
16.                 }  
17.                 catch  
18.                 {  
19.                      //("FileInUse");  
20.                     return "";  
21.                 }  
22.             }  
23.             System.IO.FileStream fs = new System.IO.FileStream(filePathName, System.IO.FileMode.Create, System.IO.FileAccess.Write);  
24.             System.IO.BinaryWriter w = new System.IO.BinaryWriter(fs);  
25.   
26.             try  
27.             {  
28.                 w.Write(objData as byte[]);  
29.             }  
30.             catch (Exception)  
31.             {  
32.             }  
33.             finally  
34.             {  
35.                 w.Close();  
36.                 fs.Close();  
37.             }  
38.             return filePathName;  
39.         }  
40.         #endregion   

1. #region 将文件转化为二进制  
2.        public static byte[] ConvertFileToByte(string fileName)  
3.        {  
4.            if (!System.IO.File.Exists(fileName))  
5.            {  
6.                return null;  
7.            }  
8.            System.IO.FileStream fs = new System.IO.FileStream(fileName, System.IO.FileMode.Open,System.IO.FileAccess.Read,FileShare.ReadWrite);  
9.            byte[] nowByte = new byte[(int)fs.Length];  
10.            try  
11.            {  
12.                fs.Read(nowByte, 0, (int)fs.Length);  
13.                return nowByte;  
14.            }  
15.            catch (Exception)  
16.            {  
17.                return null;  
18.            }  
19.            finally  
20.            {  
21.                fs.Close();  
22.            }  
23.        }  
24.        #endregion  

文件生成二进制流，二进制流生成文件