我正在尝试在 Windows 8 中使用 c# 和 oledb 写入 Paradox 数据库文件。我能够删除表、创建表并在收到错误“操作必须使用可更新查询”之前写入第一行。
我已经通过以下步骤尝试解决：1）以管理员身份运行 2）更新应用程序中的权限以确保我没有文件上的只读或存档属性 3）添加正在运行的用户权限以读取/ 写入 / 修改 db 文件所在的目录 4) 多次更改查询，以防我对查询做一些奇怪的事情
如果我根本无法写入或插入，那么上述步骤将是有意义的，但初始插入有效并且任何其他插入都会失败。
下面的代码显示了我尝试执行这些操作的当前方式，我已将其留在注释掉的部分中，以便您可以看到我还尝试过的其他内容。
public void OverwriteData(string fileName, DataTable dataToWrite)
{
//split up the filename
string path = Path.GetDirectoryName(fileName);
string file = Path.GetFileName(fileName);
//create the string for creating the table
string strTempCreate = "";
//string strTempInsert = "";
foreach (DataColumn column in dataToWrite.Columns)
{
if (strTempCreate != "")
{
strTempCreate = strTempCreate + ", ";
}
strTempCreate = strTempCreate + "[" + column.ColumnName + "]" + " char(30)";
/*if (strTempInsert != "")
{
strTempInsert = strTempInsert + ", ";
}
strTempInsert = strTempInsert + column.ColumnName;*/
}
string createTableStr = "CREATE TABLE " + file + " (" + strTempCreate + ")";
string dropTableStr = "DROP TABLE " + file;
//build the sql insert command
//string insertSql = "insert into " + file + " values ";
/*foreach (DataRow row in dataToWrite.Rows)
{
insertSql = insertSql + row.Field<string>;
}*/
string connectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path + @";Extended Properties=Paradox 5.x;";
//DataTable results = new DataTable();
using (OleDbConnection conn = new OleDbConnection(connectionString))
{
conn.Open();
OleDbCommand dbCommand = new OleDbCommand();
dbCommand.Connection = conn;
dbCommand.CommandText = dropTableStr;
try
{
dbCommand.ExecuteNonQuery();
}
catch { }
dbCommand.CommandText = createTableStr;
dbCommand.ExecuteNonQuery();
//try to do the insert
StringBuilder sb = new StringBuilder();
//make sure that the database is not readonly
FileAttributes attributes = File.GetAttributes(fileName);
if ((attributes & FileAttributes.Archive) == FileAttributes.Archive)
{
attributes = attributes & ~FileAttributes.Archive;
File.SetAttributes(fileName, attributes);
}
//then we want to try and connect to this database to put data into it
string selectSQL = "Select * from " + file;
using (var adapter = new OleDbDataAdapter(selectSQL, conn))
{
using (var builder = new OleDbCommandBuilder(adapter))
{
var destinationTable = new DataTable();
adapter.Fill(destinationTable);
destinationTable.Merge(dataToWrite,true,MissingSchemaAction.Ignore);
destinationTable.AcceptChanges();
foreach (DataRow row in destinationTable.Rows)
{
row.SetAdded();
}
builder.QuotePrefix = "[";
builder.QuoteSuffix = "]";
builder.GetInsertCommand();
adapter.Update(destinationTable);
}
}
/*foreach (DataRow row in dataToWrite.Rows)
{
sb.Clear();
sb.Append("insert into " + file + " values ('");
IEnumerable<string> fields = row.ItemArray.Select(field => field.ToString());
sb.Append(string.Join("','", fields));
sb.Append("')");
dbCommand.CommandText = sb.ToString();
dbCommand.ExecuteNonQuery();
}*/
/*sb.Clear();
sb.Append("insert into " + file);
foreach (DataRow row in dataToWrite.Rows)
{
sb.Append(" values ('");
IEnumerable<string> fields = row.ItemArray.Select(field => field.ToString());
sb.Append(string.Join("','", fields));
sb.Append("'),");
}
sb.Remove(sb.Length - 1, 1);
sb.Append(";");
dbCommand.CommandText = sb.ToString();
dbCommand.ExecuteNonQuery();
*/
}
}