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OK this may be a bit of a long one but please bear with me. I searched high and low and I can't seem to find a clear answer about my particular issue.

As the subject above states, I am using DataSets to retrieve, edit, insert and update records in a database. However all the other functions work as expected except the insert. What happens is that when I insert new records into the data set all looks fine as using the watch feature I can see the new records in the dataset. But after I end the edit, accept the changes and do the update, only one record is sent to the database. See some code below. I have used some bindings as well.

There code is split into different functions as follows: SetAdapaterCommands, FillDataSets, SendToDatabase and BindToUI. Can anyone see anything wrong?

Or is there something about how the dataset insert and update commands work that I'm missing?

I should maybe also say that I am updating another parent table before this one. Not sure if that has anything to do with it.

Start set adapter commands

Select command

#region Select Task Command
queryString = "SELECT value1, value2, value3 FROM Table1;";

taskCommand = new SqlCommand(queryString, connection);
#endregion Select Task Command

Update command

#region Update Task Command
queryString = "UPDATE Table1 SET value1 = @value1, value2 = @value2, value3 = @value3" +
              "WHERE value1 = @value1;";

taskUpdateCommand = new SqlCommand(queryString, connection);

taskUpdateCommand.Parameters.Add("@value1", SqlDbType.Char, 10, "value1");
taskUpdateCommand.Parameters.Add("@value2", SqlDbType.Char, 10, "value2");
taskUpdateCommand.Parameters.Add("@value3", SqlDbType.VarChar, 50, "value3");

taskAdapter.UpdateCommand = taskUpdateCommand;

SqlParameter taskParameter = taskUpdateCommand.Parameters.Add("@oldValue1", SqlDbType.Char, 10, "value1");
taskParameter.SourceVersion = DataRowVersion.Original;
#endregion Update Task Command

Insert command

#region Insert Task Command
queryString = "INSERT INTO Table1 (value1, value2, value3) " +
              "VALUES (@value1, @value2, @value3);";

taskInsertCommand = new SqlCommand(queryString, connection);

taskInsertCommand.Parameters.Add("@value1", SqlDbType.Char, 10, "value1");
taskInsertCommand.Parameters.Add("@value2", SqlDbType.Char, 10, "value2");
taskInsertCommand.Parameters.Add("@value3", SqlDbType.VarChar, 50, "value3");            

taskAdapter.InsertCommand = taskInsertCommand;
#endregion Insert Task Command

End set adapter commands

Fill data set

private void loadFromDatabase()
{
    #region Load Data and From Database 
    SetAdapterCommands();

    #region Load Tasks
    try
    {
        connection.Open();
        taskAdapter.SelectCommand = taskCommand;
        taskAdapter.Fill(Table1DataSet);
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
    #endregion Load Tasks
}

Send changes to database

private void updateDatabase()
{
    try
    {
        Table1BindingSource.EndEdit();
        Table1DataSet.AcceptChanges();
        taskAdapter.Update(Table1DataSet);
    }
    catch(System.Exception ex)
    {
        MessageBox.Show("Update Failed");
    }
}

Bind to UI

textBoxValue1.DataBindings.Add("Text", Table1BindingSource, "value1");
textBoxValue2.DataBindings.Add("Text", Table1BindingSource, "value2");
textBoxValue3.DataBindings.Add("Text", Table1BindingSource, "value3");
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1 回答 1

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这是一个常见的错误。数据集。AcceptChanges将 DataSet 的每个 DataTable 中每个 DataRow的RowState更改为值DataRowState.Unchanged。

因此，如果您调用AcceptChanges以下调用Update未找到任何要更新、删除或插入的行。

您应该简单地删除对AcceptChanges.

一点背景。当您编辑一行时，它RowState会更改为DataRowState.Modified（对于我们拥有的插入DataRowState.Added和删除的行，我们拥有DataRowState.Deleted）

DataAdapter 的 Update 调用搜索处于这些状态的行以准备并将相关的 UPDATE/INSERT/DELETE 发送到数据存储区。

我认为 AcceptChanges 的名称令人困惑，许多人认为在发送更新之前需要此调用，但事实恰恰相反。

于 2016-07-01T16:05:51.127 回答