Hej!
Vill ha en funktion som räknar antal poster i min databas. Hur gör jag detta? Vill sedan skriva ut detta i HTML-koden.
SQL-koden blir väl typ
SELECT COUNT (*) FROM X
SELECT (*) COUNT
3 svar · 368 visningar · startad av Topper
sub page_load
dim SQL as string = "SELECT Count(kolumn) FROM tbl"
dim CnStr as string = "Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath("db.mdb")
'felhantering med Try .. Catch
Try
dim Cn as new OleDbConnection(CnStr)
Cn.Open()
dim Cm as new OleDbCommand(SQL,Cn)
dim result as object
result = Cm.ExecuteScalar()
Cn.Close()
lbl1.Text = CStr(result)
'fånga felmeddelande
Catch ex As exception
lbl_error.Text = "Ett fel uppstod..<br />Error: " & ex.Message
End Try
end sub
Du måste sen ha två labels på din sida:
'html, body etc.
<asp:label id="lbl_error" runat="server" />
<p><asp:label id="lbl1" runat="server" /></p>
OKej, Tack...fungerar utmärkt.
Men inte om jag ska ha en till som räknar en annan tabell.
Annars va det kanon.
Vill asså har två räkningsfunktioner på samma sida...
<%@ Page Language="VB" Strict="False" Debug="True" %>
<%@ import Namespace="System.Data.OleDb" %>
<script runat="server">
sub page_load
dim SQL as string
SQL = "SELECT count(tbl_posts.tid),(SELECT count(tbl_users.uid) from tbl_users) FROM tbl_posts"
dim Cn as new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;data source=" & Server.MapPath("swedair/dbms/db_forum.mdb"))
dim Cm as new OleDbCommand(SQL,Cn)
dim dbRead as OleDbDataReader
try
Cn.Open()
dbRead = Cm.ExecuteReader()
while dbRead.Read()
l1.text = dbRead.Item(0)
l2.text = dbRead.Item(1)
end while
catch ex as exception
l3.text = "Error!"
finally
dbRead.Close()
Cn.Close
end try
end sub
</script><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="sv" xml:lang="sv">
<head>
<title>Test</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
</head>
<body>
<p><asp:literal id="l1" runat="server" /></p>
<p><asp:literal id="l2" runat="server" /></p>
<p><asp:literal id="l3" runat="server" /></p>
</body>
</html>
/r lade till ett finally-block också. Ej fått det att fungera tidigare, men man ska deklarera variabler innan ett try..catch..finally-block! :)