c# - 从数据库中获取自动编号值

Question

代码如下。在我的代码中，我更新了现有的行(从现有的表)，程序从文本框获取所有更新的值。在表的末尾(最后一列)有一个名为“codonsAutoNum”的自动编号字段

我不知道如何从数据库中获取值(自动编号值)。我需要在“??”位置(在代码中)的值。

谢谢大家的帮助!

代码:

        private void update_Click(object sender, EventArgs e)
    {
        string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Projects_2012\\Project_Noam\\Access\\myProject.accdb";
        OleDbConnection myConnection = new OleDbConnection(connectionString);
        string myInsertQuery =(String.Format("UPDATE tblCodons SET codonsCodon1='{0}', codonsCodon3='{1}', " + 
        "codonsTriplet1='{2}', codonsTriplet2='{3}', codonsTriplet3='{4}', codonsTriplet4='{5}', " + 
        "codonsTriplet5='{6}', codonsTriplet6='{7}', codonsFullName='{8}'" + 
        " WHERE codonsAutoNum='{9}'",codon1.Text, codon3.Text ,triplet1.Text, triplet2.Text,
         triplet3.Text, triplet4.Text, triplet5.Text, triplet6.Text,
        fullName.Text,??));
        OleDbCommand myCommand = new OleDbCommand(myInsertQuery);
        myCommand.Connection = myConnection;
        myConnection.Open();
        myCommand.ExecuteNonQuery();
        myCommand.Connection.Close();

编辑:它真的很困惑。我的代码应该如何显示？我需要把“SELECT @@identity”放在哪里？我不明白为什么我不能只取值？(我需要它作为所选行的索引来确定更新的位置。当我识别这个(下面)时它运行良好但它不允许我更改全名字段..有比自动编号列更好的解决方案？

        private void update_Click(object sender, EventArgs e)
    {


        string connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Projects_2012\\Project_Noam\\Access\\myProject.accdb";

        OleDbConnection myConnection = new OleDbConnection(connectionString);
        string myInsertQuery =(String.Format("UPDATE tblCodons SET codonsCodon1='{0}', codonsCodon3='{1}', " + 
        "codonsTriplet1='{2}', codonsTriplet2='{3}', codonsTriplet3='{4}', codonsTriplet4='{5}', " + 
        "codonsTriplet5='{6}', codonsTriplet6='{7}', codonsFullName='{8}'" + 
        " WHERE codonsFullName = {9}",codon1.Text, codon3.Text ,triplet1.Text, triplet2.Text,
         triplet3.Text, triplet4.Text, triplet5.Text, triplet6.Text,
        fullName.Text,this.name));
        OleDbCommand myCommand = new OleDbCommand(myInsertQuery);
        myCommand.Connection = myConnection;
        myConnection.Open();
        myCommand.ExecuteNonQuery();
        myCommand.Connection.Close();
        this.tblCodonsTableAdapter.Fill(this.myProjectDataSet.tblCodons);

name= fullname 保存的值，每次点击值变化

还有一个问题。我尝试对 e.Row 做同样的事情(我在每次点击表格时都保存了它)但我收到错误“System.Data.OleDb.OleDbException (0x80004005): can caue a duplicated values on the index,or on the mainKey还是在关系中”

Answer 1

看这个:

http://msdn.microsoft.com/en-us/library/ks9f57t0(v=VS.80).aspx

请参阅标有“检索 Microsoft Access 自动编号值”的部分

排序版本

OleDbCommand cmdNewID = new OleDbCommand("SELECT @@IDENTITY",
            connection)

我不相信 SCOPE_IDENTITY() 存在于 access 中