关于文件保存到Oracle中BLOB字段的方法及例子

关于文件保存到Oracle中BLOB字段的方法及例子

1. public class FileOpClass  
2.     {  
3.         public static byte[] GetFileStream(string filepath)  
4.         {  
5.             byte[] byteArray = null;  
6.             FileStream fs = null;  
7.             try  
8.             {  
9.                 fs = new FileStream(filepath, FileMode.Open);  
10.                 long filelength = fs.Length;  
11.                 byteArray = new byte[filelength];  
12.                 fs.Read(byteArray, 0, byteArray.Length);  
13.             }  
14.             catch (Exception ee)  
15.             {  
16.             }  
17.             finally  
18.             {  
19.                 if (fs != null)  
20.                 {  
21.                     fs.Close();  
22.                     fs.Dispose();  
23.                     fs = null;  
24.                 }  
25.             }  
26.             return byteArray;              
27.         }  
28.         public static void WriteToFile(byte[] byteArray, string filepath)  
29.         {  
30.             if (System.IO.File.Exists(filepath) == true)  
31.             {  
32.                 try  
33.                 {  
34.                     System.IO.File.Delete(filepath);  
35.                 }  
36.                 catch { }                  
37.             }  
38.             FileStream fs = null;  
39.             try  
40.             {  
41.                 fs = new FileStream(filepath, FileMode.OpenOrCreate);  
42.                 fs.Write(byteArray, 0, byteArray.Length);  
43.                 fs.Flush();  
44.             }  
45.             catch (Exception ee)  
46.             {  
47.             }  
48.             finally  
49.             {  
50.                 if (fs != null)  
51.                 {  
52.                     fs.Close();  
53.                     fs.Dispose();  
54.                     fs = null;  
55.                 }  
56.             }  
57.         }  
58.     }  
59. //------------------------------------------   
60. 先插入一条objblob字段为空的记录，用insert into tablename(objid,objname) values('xxx','yyyy');  
61. 然后对objblog字段作update方式操作  
62. //------------------------------------------   
63. byte[] byteArray =FileOpClass.GetFileStream(path);    
64. object UpdateBLOBFdValue=byteArray;               
65.                       
66. //------------------------------------------   
67. //更新BLOB字段值的方法   
68. //------------------------------------------   
69. public bool UpdateBLOBFieldValue(string UpdateTableName, string UpdateBLOBFieldName, object UpdateBLOBFdValue, string WhereEqFieldName, string WhereEqFdValue)  
70. {  
71.             bool rbc = false;  
72.             DatabaseHelperClass dbh = new DatabaseHelperClass(m_Database);  
73.             DbConnection dbconn = null;  
74.             DbTransaction dbtrans = null;  //Provider=OraOleDb.Oracle;   
75.             DbCommand dbCmd1 = null;  
76.             try  
77.             {  
78.                 dbconn = dbh.db.CreateConnection();  
79.                 if (dbconn.State != ConnectionState.Open)  
80.                 {  
81.                     dbconn.Open();  
82.                 }  
83.                 dbtrans = dbconn.BeginTransaction();  
84.   
85.                 string PrixChar = dbh.PrixChar;  
86.                 string x = "update " + UpdateTableName + " set " + UpdateBLOBFieldName + "=" + PrixChar + "Img where " + WhereEqFieldName + "=" + PrixChar + "tmpguid ";  
87.                 byte[] byteArray = UpdateBLOBFdValue as byte[];  
88.                 //   
89.                 dbCmd1 = dbconn.CreateCommand();  
90.                 dbCmd1.CommandText = x;  
91.                 dbCmd1.CommandType = CommandType.Text;  
92.                 dbCmd1.Connection = dbconn;  
93.                 dbCmd1.Transaction = dbtrans;  
94.                 //   
95.                 DbParameter dbparam = dbh.CreateParameter("" + PrixChar + "Img", byteArray);  
96.                 dbparam.Direction = ParameterDirection.Input;  
97.                 dbparam.DbType = System.Data.DbType.Binary;  
98.                 dbparam.Value = byteArray;  
99.                 dbCmd1.Parameters.Add(dbparam);  
100.                 dbCmd1.Parameters.Add(dbh.CreateParameter("" + PrixChar + "tmpguid", WhereEqFdValue));  
101.                 if (dbCmd1.ExecuteNonQuery() > 0)  
102.                 {  
103.                     rbc = true;  
104.                     dbtrans.Commit();  
105.                 }  
106.             }  
107.             catch (Exception ee)  
108.             {  
109.                 if (dbtrans != null)  
110.                 {  
111.                     dbtrans.Rollback();  
112.                 }  
113.                 rbc = false;  
114.             }  
115.             finally  
116.             {  
117.                 if (dbCmd1 != null)  
118.                 {  
119.                     dbCmd1.Dispose();  
120.                     dbCmd1 = null;  
121.                 }  
122.                 //----   
123.                 if (dbtrans != null)  
124.                 {  
125.                     dbtrans.Dispose();  
126.                     dbtrans = null;  
127.                 }  
128.                 if (dbconn != null)  
129.                 {  
130.                     dbconn.Dispose();  
131.                     dbconn = null;  
132.                 }  
133.             }  
134.             return rbc;  
135. }  
136. ----the---end-------