如何用c＃代码替换现有的ms访问数据库？

Question

String baseDirectory = @"F:\Backup";
String mdbSourceFilePath = @"D:\Db\abc.mdb";
String mdbTargetFileName = "abc.mdb";

String fullDirectory = Path.Combine(baseDirectory, DateTime.Today.ToString("dddd"));

if (!Directory.Exists(baseDirectory))
    Directory.CreateDirectory(baseDirectory);

if (!Directory.Exists(fullDirectory))
    Directory.CreateDirectory(fullDirectory);

String mdbTargetFilePath = Path.Combine(fullDirectory, mdbTargetFileName);
File.Copy(mdbSourceFilePath, mdbTargetFilePath);

这是用于备份数据库。如果我单击备份按钮，则会创建备份数据库，但如果再次单击它，则不会覆盖现有数据库。我想替换现有的数据库。

Answer 1

尝试检查该文件是否存在 if (File.Exists(fileName)) 然后你可以使用 File.Replace方法

Answer 2

There is a third (optional) argument to File.Copy called overwrite. Set it to true to overwrite an existing file, as long as it isn't read-only:

File.Copy(mdbSourceFilePath, mdbTargetFilePath, overwrite: true);

An alternative would be to check if mdbTargetFilePath exists and delete it prior to the copy:

if (File.Exists(mdbTargetFilePath))
{
    File.Delete(mdbTargetFilePath);
}