基于下拉列表选择值的文本框消息

Question

我的下拉列表有值，用户选择 A1，文本框将显示 +1，选择 A2，消息显示 +2，如果 B1，消息显示 -1，B2 消息显示 -2。我选择 A1，+1 出来，A2，+2 出现。但是，当我选择 B1 时，出现 +1 和 B2，+2。为什么 As 答案只出现而不出现 Bs ？需要帮助。

我的 aspx.cs

protected void ddlJM1_SelectedIndexChanged(object sender, EventArgs e)
{
    int IntentID = Convert.ToInt32(ddlJM1.SelectedValue.ToString());
    FillYes(IntentID);

    if (ddlJM1.SelectedIndex == 1)
    {
        ddlJM2.Enabled = true;
        ddlJM3.Enabled = false;
        ddlJM2.SelectedIndex = 0;
        lblMsgJM.Text = "";
    }

    if (ddlJM1.SelectedIndex == 2)
    {
        ddlJM2.Enabled = true;
        ddlJM2.SelectedIndex = 0;

        ddlJM3.Enabled = false;
        lblMsgJM.Text = "";
    }

}

protected void ddlJM2_SelectedIndexChanged(object sender, EventArgs e)
{
    int YesID = Convert.ToInt32(ddlJM2.SelectedValue.ToString());
    FillJob(YesID);

    if (ddlJM2.SelectedIndex == 1)
    {
        ddlJM3.Enabled = true;
        lblMsgJM.Text = "";
    }

    if (ddlJM2.SelectedIndex == 2)
    {
        ddlJM3.Enabled = false;

    }

    if (ddlJM2.SelectedIndex == 3)
    {
        ddlJM3.Enabled = true;
        lblMsgJM.Text = "";
    }

    if (ddlJM2.SelectedIndex == 4)
    {
        ddlJM3.Enabled = false;
        lblMsgJM.Text = "Please consult / review with ODD focal person";
    }

}


 protected void ddlJM3_SelectedIndexChanged(object sender, EventArgs e)
{
    if (ddlJM3.SelectedIndex == 1)
    {
        lblMsgJM.Text = "+1";
    }
    if (ddlJM3.SelectedIndex == 2)
    {
        lblMsgJM.Text = "+2";
    }

     if (ddlJM3.SelectedIndex == 3)
    {
        lblMsgJM.Text = "-1";
    }
    if (ddlJM3.SelectedIndex == 4)
    {
        lblMsgJM.Text = "-2";
    }
}

 private void FillJob(int YesID) //for ddlJM3
    {
        string strConn = ConfigurationManager.ConnectionStrings["dbconnection"].ConnectionString;
        SqlConnection con = new SqlConnection(strConn);
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandType = CommandType.Text;
        cmd.CommandText = "SELECT AlphabetID, Alphabet FROM TableJob WHERE YesID =@YesID";
        cmd.Parameters.AddWithValue("@YesID", YesID);
        DataSet objDs = new DataSet();
        SqlDataAdapter dAdapter = new SqlDataAdapter();
        dAdapter.SelectCommand = cmd;
        con.Open();
        dAdapter.Fill(objDs);
        con.Close();

        if (objDs.Tables[0].Rows.Count > 0)
        {
            ddlJM3.DataSource = objDs.Tables[0];
            ddlJM3.DataTextField = "Alpahabet";
            ddlJM3.DataValueField = "AlphabetID";
            ddlJM3.DataBind();
            ddlJM3.Items.Insert(0, "--Select--");

        }

     }

Answer 1

请像这样比较选择的值

protected void ddlJM3_SelectedIndexChanged(object sender, EventArgs e)
{
    if (ddlJM3.SelectedItem.Text.ToLower() == "a1")
    {
        lblMsgJM.Text = "+1";
    }
    if (ddlJM3.SelectedItem.Text.ToLower() == "a2")
    {
        lblMsgJM.Text = "+2";
    }

    if (ddlJM3.SelectedItem.Text.ToLower() == "b1")
    {
        lblMsgJM.Text = "-1";
    }
    if (ddlJM3.SelectedItem.Text.ToLower() == "b2")
    {
        lblMsgJM.Text = "-2";
    }
}