protected void Button1_Click(object sender, EventArgs e)
{ DataTable table = com.panduandenlu(username.Text, pwd.Text);//从用户表中取用户=username.Text密码=pwd.Text的记录
try
{
if (username.Text == "" || username.Text != table.Rows[0]["username"].ToString() || pwd.Text != table.Rows[0]["pwd"].ToString() || code.Text == "" || code.Text != Session["codema"].ToString())
{
com.WebMessageBox("抱歉!登陆失败,请重试!", Request.Url.ToString());
return;
}
}
catch
{
com.WebMessageBox("登陆失败,请重试!",Request.Url.ToString()); //
return;
}
Session["username"] = username.Text;
this.stateLb.Text = table.Rows[0]["state"].ToString();
Session["state"] = table.Rows[0]["state"].ToString();
this.logintable.Visible = false;
this.loginInTbl.Visible = true;
this.usernameLb.Text = table.Rows[0]["username"].ToString();
com.WebMessageBox("!恭喜你,登陆成功!", Request.Url.ToString());
}
public void WebMessageBox(string values, string PageURL)
{
HttpContext.Current.Response.Write("<script>alert('" + values + "');window.location.href='" + PageURL + "'</script>");
HttpContext.Current.Response.End();
}代码是网上下来的问题: 请问这个catch捕获的是什么异常。
{
if (username.Text == "" || username.Text != table.Rows[0]["username"].ToString() || pwd.Text != table.Rows[0]["pwd"].ToString() || code.Text == "" || code.Text != Session["codema"].ToString())
{
com.WebMessageBox("抱歉!登陆失败,请重试!", Request.Url.ToString());
return;
}
}
这里面的异常
{
if (username.Text == "" || username.Text != table.Rows[0]["username"].ToString() || pwd.Text != table.Rows[0]["pwd"].ToString() || code.Text == "" || code.Text != Session["codema"].ToString())
{
com.WebMessageBox("抱歉!登陆失败,请重试!", Request.Url.ToString());
return;
}
}
这个会发生什么异常吗?
会比较慢的
情况都可以判断的出来。
if(table==null || table.rows.count==0)
{
//登陆失败
return;
}
if (username.Text == "" || username.Text != table.Rows[0]["username"].ToString() || pwd.Text != table.Rows[0]["pwd"])
{
//登陆失败
return;
}