Use. Net to operate access databases

Use. Net to operate access databases (create, compress, back up, and restore components)
Write a smallProgramThere is no Microsoft Access at hand. It is still easy to create a database.
First, reference c: \ Program Files \ common files \ System \ ADO \ msadox. dll, which contains the ADOX namespace;
Then reference c: \ Program Files \ common files \ System \ ADO \ msjro. dll, which contains the jro namespace
Note: For example, if the DLL Import fails, manually import the COM component as a. NET Component and use the vs.net tool to import it.

Using system;
Using system. IO;
Using ADOX; // This namespace contains the class (method) for creating access)-- Solution ==> reference ==> add reference ==> visit to find. dll
Using jro; // The namespace contains the class (method) for compressing access)

Public class access
{
/// Create an Access database based on the specified file name
/// Mdbpath: the absolute access path of the file to be created
 Public void create (string mdbpath)
{
If (file. exists (mdbpath) // check whether the database already exists
{
Throw new exception ("the target database already exists and cannot be created ");
}
// You can add a password so that the created database can be opened only after the password is entered.
Mdbpath = "provider = Microsoft. Jet. oledb.4.0; Data Source =" + mdbpath;
// Create an instance of the catalogclass object,
ADOX. catalogclass cat = new ADOX. catalogclass ();
// Use the create method of the catalogclass object to create an Access database
Cat. Create (mdbpath );
}

/// Compress and fix the ACCESS database. The mdbpath is the absolute path of the database.
Public void compact (string mdbpath)
{
If (! File. exists (mdbpath )) // Check whether the database already exists
{
Throw new exception ("the target database does not exist and cannot be compressed ");
}
// Declare the temporary database name
String temp = datetime. Now. year. tostring ();
Temp + = datetime. Now. Month. tostring ();
Temp + = datetime. Now. Day. tostring ();
Temp + = datetime. Now. Hour. tostring ();
Temp + = datetime. Now. Minute. tostring ();
Temp + = datetime. Now. Second. tostring () + ". Bak ";
Temp = mdbpath. substring (0, mdbpath. lastindexof ("\") + 1) + temp;
// Define the connection string of the temporary database
Temp2 = "provider = Microsoft. Jet. oledb.4.0; Data Source =" + temp;
// Define the connection string of the target database
Mdbpath2 = "provider = Microsoft. Jet. oledb.4.0; Data Source =" + mdbpath;
// Create an instance of the jetengineclass object
Jro. jetengineclass Jt = new jro. jetengineclass ();
// Use the compactdatabase method of the jetengineclass object to compress and restore the database
JT. compactdatabase (mdbpath2, temp2 );
// Copy the temporary database to the target database (overwrite)
File. Copy (temp, mdbpath, true );
// Delete the temporary database
File. Delete (temp );
}

/// Backup database, mdb1, absolute path of the source database; mdb2: absolute path of the target database
Public void backup (string mdb1, string mdb2)
{
If (! File. exists (mdb1 ))
{
Throw new exception ("the source database does not exist ");
}
Try
{
File. Copy (mdb1, mdb2, true );
}
Catch (ioexception IXP)
{
Throw new exception (IXP. tostring ());
}
}

/// Restore the database. mdb1 indicates the absolute path of the backup database, and mdb2 indicates the absolute path of the current database.
Public void recover (string mdb1, string mdb2)
{
If (! File. exists (mdb1 ))
{
throw new exception ("the backup database does not exist ");
}
try
{
File. copy (mdb1, mdb2, true);
}
catch (ioexception IXP)
{
throw new exception (IXP. tostring ();
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