登录问题
string name =this.textBox1.ToString().Trim();
string pwd = this.textBox2.ToString().Trim();
string contr = "Data Source=.;Initial Catalog=ptang;Integrated Security=True";
using (SqlConnection con = new SqlConnection(contr)) {
con.Open();
string sql = "select * from School where username='" + name + "'";
using (SqlCommand cmd = new SqlCommand(sql,con)) {
using (SqlDataReader reader = cmd.ExecuteReader()) {
if (reader.Read())
{
string dbpwd = reader.GetString(reader.GetOrdinal("password"));
if (pwd == dbpwd)
{
MessageBox.Show("登录成功!");
}
else {
MessageBox.Show("密码错误");
}
}
else {
MessageBox.Show("用户名错误!");
}
连接数据库登录,其中数据库字段及数据类型
username varchar(20),password varchar(50)
每次输入用户名与密码都弹出“用户名错误”.怎么会每次都没有查询到用户名,是数值类型的关系吗