C＃asp.net字符串比較

Question

這是我的C＃代碼

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
    TextBox25.Text = DateTime.Now.ToString("MM/yy");

    SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["preconn"].ToString());

    con.Open();

    SqlCommand com = new SqlCommand("select * from employe Where user_id = '" + DropDownList1.SelectedItem.Value + "'", con);

    SqlDataReader reader = com.ExecuteReader();

    if (reader.Read())
    {
        TextBox1.Text = reader["Id"].ToString();
    }
    con.Close();
}

protected void Button1_Click(object sender, EventArgs e)
    {

        string user1 = Convert.ToString(TextBox25.Text);

        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["preconn"].ToString());

        con.Open();

        SqlCommand com2 = new SqlCommand("select * from salary where id='" + DropDownList1.SelectedItem.Text + "'", con);

        SqlDataReader reader1 = com2.ExecuteReader();

        if (reader1.Read())
        {
            string user;
            user = Convert.ToString(reader1["month"]);

            //if (TextBox25.Text == user)
            if (user1.CompareTo(user)==0)
            {
                Label9.Visible = true;
                Label9.Text = "Salary already updated please check again";
            }
        }// user check end

        else
        {

            SqlCommand com1 = new SqlCommand("insert into salary values(@id,@work_days,@month)",con);

            SqlParameter obj1 = new SqlParameter("@id", DbType.StringFixedLength);
            obj1.Value = DropDownList1.SelectedItem.Value;
            com1.Parameters.Add(obj1);

            SqlParameter obj2 = new SqlParameter("@work_days", DbType.StringFixedLength);
            obj2.Value = TextBox10.Text;
            com1.Parameters.Add(obj2);

            SqlParameter obj15 = new SqlParameter("@month", DbType.StringFixedLength);
            obj15.Value = TextBox25.Text;
            com1.Parameters.Add(obj15);

            com1.ExecuteNonQuery();

            con.Close();


        }

    }

當我單擊Button1時，沒有插入數據並且沒有錯誤消息顯示。 我認為問題是在我的情況下，如果（user1.CompareTo（user）== 0）

我正在使用SQL Server 2008 Visual Studio 2010

Answer 1

我認為你必須做這樣的事情

 user = Convert.ToString(reader1['rowIndex']["month"]);

其中RowIndex是整數