在按提交按钮前检查用户名是否存在
本文关键字:用户 是否 存在 检查 提交 按钮 | 更新日期: 2023-09-27 18:03:42
我有以下代码:
protected void cmdSave_Click(object sender, EventArgs e)
{
string sFilePath = Server.MapPath("Database3.accdb");
OleDbConnection Conn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + sFilePath + ";Persist Security Info=False;");
using (Conn)
{
Conn.Open();
OleDbCommand myCommand = new OleDbCommand("SELECT COUNT(*) FROM colaborador WHERE username=@username", Conn);
myCommand.Parameters.Add("?", OleDbType.VarChar).Value = HttpContext.Current.User.Identity.Name;
int totalRegistos = (int)myCommand.ExecuteScalar();
if (totalRegistos > 0)
{
// user already answered
lblInfo0.Text = "The user already asnwered";
}
else
{
// the user didn't asnwered
string insertCmd = "INSERT INTO colaborador(Empresa,Empresa2,Telemovel,username) VALUES (@Empresa,@Empresa2,@Telemovel,@username)";
// insere na tabela colaborador os campos empresa, empres2, user os valores @
{
OleDbCommand myCommand2 = new OleDbCommand(insertCmd, Conn);
myCommand2.Parameters.AddWithValue("@Empresa", empresa.Text);
myCommand2.Parameters.AddWithValue("@Empresa2", empresa2.Text);
myCommand2.Parameters.AddWithValue("@Telemovel", telemovel.Text);
myCommand2.Parameters.AddWithValue("@username", HttpContext.Current.User.Identity.Name);
Response.Write(myCommand.ExecuteNonQuery());
lblInfo.Text = "Data saved!";
lblInfo.ForeColor = System.Drawing.Color.Green;
}
}
}
}
这个工作正常,没有错误,并保存到数据库中,如果用户名存在,说一个消息"用户已经回答"
然而我需要按下提交按钮。
有任何方式说消息(如果用户名已经存在)之前字段的文本框?我如何修改代码来做到这一点?
if (!IsPostBack)
{
string sFilePath = Server.MapPath("Database3.accdb");
OleDbConnection Conn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + sFilePath + ";Persist Security Info=False;");
using (Conn)
{
Conn.Open();
OleDbCommand myCommand = new OleDbCommand("SELECT COUNT(*) FROM colaborador WHERE username=@username", Conn);
myCommand.Parameters.Add("?", OleDbType.VarChar).Value = HttpContext.Current.User.Identity.Name;
int totalRegistos = (int)myCommand.ExecuteScalar();
if (totalRegistos > 0)
{
// Já registado
lblInfo0.Text = "O username já existe na base de dados";
empresa.Enabled = false;
empresa2.Enabled = false;
telemovel.Enabled = false;
cmdSave.Visible = false;
}
}
}