Redigera

Dela via


OracleBFile.SetFileName(String, String) Method

Definition

Binds the OracleBFile object to a different file in the operating system.

public:
 void SetFileName(System::String ^ directory, System::String ^ file);
public void SetFileName (string directory, string file);
member this.SetFileName : string * string -> unit
Public Sub SetFileName (directory As String, file As String)

Parameters

directory
String

The alias of the directory object that contains a physical file.

file
String

The name of the file in the operating system.

Exceptions

The operation must be within a transaction.

Remarks

The SetFileName operation must be within a transaction to succeed. Simply calling SetFileName on a BFILE associates the OracleBFile object with a different file, but does not update the Oracle table. To update the Oracle table after calling SetFileName, you must call the Update method of the OracleDataAdapter and then commit the transaction.

Once you retrieve the DirectoryName or FileName property, they are cached in the OracleBFile object and are unaffected by any cloned OracleBFile objects' calls to SetFileName, or by any changes to the BFILE in the database. In other words, they might not represent the actual values of the BFILE object in the server.

Furthermore, retrieving either property (DirectoryName or FileName) causes both property values to be retrieved from the server and cached in the OracleBFile object.

The following C# example assumes this schema in an Oracle table:

(col1 number, col2 BFILE)  

The example demonstrates using the SetFileName, Read and Seek methods to access an OracleBFile object.

byte[] buffer = new byte[100];  
OracleDataReader dataReader = command.ExecuteReader();  
using (dataReader) {  
    if (dataReader.Read()) {  
        OracleBFile BFile = dataReader.GetOracleBFile(1);  
        using (BFile) {  
            BFile.Seek(0, SeekOrigin.Begin);  
            BFile.Read(buffer, 0, 100);  
            command.Transaction = connection.BeginTransaction();  
            BFile.SetFileName("TESTDIR", "File1.jpg");  
            BFile.Read(buffer, 0, 100);  
        }  
    }  
}  

Applies to