Title: Params in a Web-Query at run time
Question: Property editors are fine, but code is more readable and maintainable if we put the data out from TQuery's ressource direct in the implementation section. So the serialisation is important.
Answer:
1. It's important to assign the query first (SQL:= aQuery) and second assign the Params including definition of dataType:
procedure TModWebBroker.execWebQuerySQL;
var
aQuery: TStringList;
begin
try
aQuery:= TStringList.Create;
aQuery.clear;
Build_kontoSQLString(aQuery);
with qryWebCust do begin
SQL.Clear;
SQL:= aQuery;
params[0].name:='clientname';
params[0].dataType:=ftstring;
OPEN;
end; //with
finally
aQuery.Free;
end; //try
end;
2. We build the query in a own procedure, so it's open for change (programming for change ;)):
procedure TModWebBroker.Build_kontoSQLString(var aQuery: TStringList);
begin
with aQuery do begin
Add('SELECT cust_no, customer, descript, amount');
Add('FROM account, customer, acctype');
Add('WHERE account.cust_no = customer.cust_no');
Add('AND account.acc_type = acctype.acc_id');
Add('AND UPPER(customer) LIKE UPPER(:clientname)||'#39'%'#39);
Add('ORDER BY amount');
end;
end;
3. We get the parameter from a browser through a request-object in a ISAPI-DLL:
(The example "webqueries" is available on the net,now)
procedure TModWebBroker.kontoStand1Action(Sender: TObject;
Request: TWebRequest; Response: TWebResponse;
var Handled: Boolean);
var
paraField: string;
begin
with qrywebAccount do begin
paraField:=(Request.QueryFields.Values['clientname']);
if Pos (uppercase(paraField), uppercase(Content)) 1 then
Response.Content:= Content
else
Response.Content:= Format('Client"%s" not found!'
+ '',
[Request.QueryFields.Values['clientname']]);
end; //qrywebAccount
end;
last tip:
after an insert you can get the last primary key without a stored procedure:
function GetGenID (const AGeneratorName: string): integer;
begin
with TFIBQuery.Create(NIL) do
try
Database:= ibDB;
SQL.Text:= 'SELECT GEN_ID ('
+ AGeneratorName + ', 1) from rdb$database';
ExecQuery;
Result:= Fields [0].AsInteger;
Close;
finally
Free;
end;
end;