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我从以下代码中遗漏了什么?在这个代码片段中,我正在从 SQLite 数据库中读取一个表。然后我更新一个单元格,然后读回更改。

此代码是较大代码的简化版本,但它说明了问题。

代码可以完美地读取表格,但是 AcceptChanges() 不会写回任何内容。我通过重复阅读并转到 SQLiteAdmin 并仔细阅读表格来验证这一点。

我尝试添加“oLocalAdapter.Update(oLocalSet.Tables[0]);” 线,但这并没有任何区别。我看到那个正在搜索。

using System.Data.SQLite;

// DATABASE (Local): Formulate the SQL command.
String strSqlCommand = "SELECT * FROM [tblTest] ORDER BY [IdPrimary] ASC;";
SQLiteCommand oLocalCommand = new SQLiteCommand(strSqlCommand, ClassEngine.Connection);

// DATABASE (Local): Get the data records.
SQLiteDataAdapter oLocalAdapter = new SQLiteDataAdapter(oLocalCommand);
DataSet oLocalSet = new DataSet();
oLocalAdapter.Fill(oLocalSet, "tblTest");

// Try to write to some changes.
String strValue = oLocalSet.Tables[0].Rows[0][8].ToString();
oLocalSet.Tables[0].Rows[0][8] = 9;
oLocalSet.Tables[0].AcceptChanges();
oLocalAdapter.Update(oLocalSet.Tables[0]);

// Clean up.
oLocalSet.Dispose();
oLocalAdapter.Dispose();
oLocalCommand.Dispose();
oLocalCommand = null;
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2 回答 2

3

好,知道了。

一,我不得不重新定位/修改 AcceptChanges() 行。

这包括可能的线路

oLocalAdapter.AcceptChangesDuringUpdate = true;

然后我不得不添加

SQLiteCommandBuilder oBuilder = new SQLiteCommandBuilder(oLocalAdapter);
oLocalAdapter.UpdateCommand = oBuilder.GetUpdateCommand();

最后一行是更新,它可以工作。这使得代码:

// DATABASE (Local): Formulate the SQL command.
String strSqlCommand = "SELECT * FROM tblTest ORDER BY IdPrimary ASC;";
SQLiteCommand oLocalCommand = new SQLiteCommand(strSqlCommand, ClassEngine.Connection);

// DATABASE (Local): Get the data records.
SQLiteDataAdapter oLocalAdapter = new SQLiteDataAdapter(oLocalCommand);
DataSet oLocalSet = new DataSet();
oLocalAdapter.Fill(oLocalSet, "tblTest");

// 
SQLiteCommandBuilder oBuilder = new SQLiteCommandBuilder(oLocalAdapter);

// Try to write to some changes.
String strValue = oLocalSet.Tables[0].Rows[0][8].ToString();
oLocalSet.Tables[0].Rows[0][8] = 9;
strValue = oLocalSet.Tables[0].Rows[0][8].ToString();
oLocalSet.AcceptChanges();
oLocalAdapter.UpdateCommand = oBuilder.GetUpdateCommand();
oLocalAdapter.Update(oLocalSet.Tables[0]);

// Clean up.
oLocalSet.Dispose();
oLocalAdapter.Dispose();
oLocalCommand.Dispose();
oLocalCommand = null;
于 2013-05-10T15:53:36.920 回答
0
public void SaveDataTable(DataTable DT)
        {
        try
            {
            con.Open();
            cmd = con.CreateCommand();
            cmd.CommandText = string.Format("SELECT * FROM {0}", DT.TableName);
            adapter = new SQLiteDataAdapter(cmd);
            SQLiteCommandBuilder builder = new SQLiteCommandBuilder(adapter);
            adapter.Update(DT);
            con.Close();
            }
        catch (Exception Ex)
            {
            System.Windows.MessageBox.Show(Ex.Message);
            }
于 2016-12-29T19:59:49.490 回答