این void رو من ازش استفاده می کنم :
void search()
{
con.Close();
string query = null;
try
{
switch (comboBox1.Text)
{
case "کد کاربر": { query = "SELECT * FROM [user] WHERE [کد کاربر] LIKE '" + textBoxX8.Text + "%'"; break; }
case "نام کاربری": { query = "SELECT * FROM [user] WHERE [نام کاربری] LIKE '" + textBoxX8.Text + "%'"; break; }
case "نام": { query = "SELECT * FROM [user] WHERE [نام] like '" + textBoxX1.Text + "%'"; break; }
case "نام خانوادگی": { query = "SELECT * FROM [user] WHERE [نام خانوادگی] like '" + textBoxX8.Text + "%'"; break; }
case "نوع کاربر": { query = "SELECT * FROM [user] WHERE [نوع کاربر] like '" + textBoxX8.Text + "%'"; break; }
case "تلفن": { query = "SELECT * FROM [user] WHERE [تلفن] like '" + textBoxX8.Text + "%'"; break; }
case "تلفن همراه": { query = "SELECT * FROM [user] WHERE [تلفن همراه] like '" + textBoxX8.Text + "%'"; break; }
default: { break; }
}
con.Open();
OleDbCommand command = new OleDbCommand();
command.CommandText = query;
command.Connection = con;
OleDbDataAdapter adapter = new OleDbDataAdapter();
adapter.SelectCommand = command;
DataTable objDataTable = new DataTable();
adapter.Fill(objDataTable);
con.Close();
dataGridViewX1.DataSource = objDataTable;
}
catch
{
con.Close();
}
}