 |
BorlandTalk.com
Borland discussion newsgroups
|
| View previous topic :: View next topic |
| Author |
Message |
Mark Shapiro
Guest
|
 Posted: Fri Jan 28, 2005 3:33 pm Post subject: Referencing a stringlist by name |
 |
|
I would like to create a generic test routine that checks whether or
not any of a series of TStringLists contains any text. How can I
duplicate the following type of functionality for a TStringList? At
runtime, the name of the list will be contained in the CTable
"control_name" field.
if (FindComponent(CTable.FieldByName('control_namel').asString) as
TRichEdit).Text = '' then
Result := false;
|
|
| Back to top |
|
 |
Tom de Neef
Guest
|
| Posted: Fri Jan 28, 2005 5:53 pm Post subject: Re: Referencing a stringlist by name |
|
|
"Mark Shapiro" <infocus (AT) swbell (DOT) net> schreef in bericht
news:5dmkv05bpdi3u25co0p979uglqssh83r5l (AT) 4ax (DOT) com...
| Quote: | I would like to create a generic test routine that checks whether or
not any of a series of TStringLists contains any text. How can I
duplicate the following type of functionality for a TStringList? At
runtime, the name of the list will be contained in the CTable
"control_name" field.
if (FindComponent(CTable.FieldByName('control_namel').asString) as
TRichEdit).Text = '' then
Result := false;
|
A Tstringlist has a 'text' property: this lists the strings in the object as
a single string with the individual strings delimited by carriage returns
and line feeds. So, checking for the presence of a refString within one
Tstringlist can be done via:
result:= NOT pos(refString,myStringlist.text);
or one of the more general string searching functions if you do not care
about uppercase/lowercase.
When you have a series of Tstringlists, the above can be extended to:
result:=true;
for k:=0 to series.count-1 do
if pos(refString,Tstringlist(series[k]).text)
then exit;
result:=false;
You will have to store the stringlists in Series:
var series : Tlist;
begin
series:=Tlist.create;
series.add(firstStringlist);
series.add(secondStringlist);
....
or a more appropriate way of identifying them and storing them in the Series
list.
Tom
|
|
| Back to top |
|
|
Mark Shapiro
Guest
|
| Posted: Fri Jan 28, 2005 9:43 pm Post subject: Re: Referencing a stringlist by name |
|
|
Thank you Tom. What I'm looking for is a bit different: how to
reference a StringList programmatically when I won't know its name
until runtime.
if SomeStringList.Text = '' then
Result := false;
I have the name of the StringList variable as a string. How do I cast
it or otherwise reference it to achieve the functionality of the code
above?
|
|
| Back to top |
|
|
Tom de Neef
Guest
|
| Posted: Fri Jan 28, 2005 10:24 pm Post subject: Re: Referencing a stringlist by name |
|
|
"Mark Shapiro" <infocus (AT) swbell (DOT) net> schreef in bericht
news:68clv0d3v5qcdl7ia46icssi55g024rifq (AT) 4ax (DOT) com...
| Quote: | Thank you Tom. What I'm looking for is a bit different: how to
reference a StringList programmatically when I won't know its name
until runtime.
if SomeStringList.Text = '' then
Result := false;
I have the name of the StringList variable as a string. How do I cast
it or otherwise reference it to achieve the functionality of the code
above?
|
Somehow, its name should be stored somewhere.
Suppose you get it from a database, where the list of strings is returned as
the result of a query. In the query you specify the name, or the name is
returned as well.
var
listOfTables : Tstringlist;
aTable : Tstringlist;
tableName : string;
begin
listOfTables:=Tstringlist.create;
...
//get your table from somwhere
aTable:=Tstringlist.create;
fillTheTable(tableName,aTable); // returns name and list
// add name to ListOfTables
ListOfTables.add(tableName);
// associate the table with this name
ListOfTables.objects[ListOfTables.count-1]:=aTable;
...
// check if string is present - to be packed in a function
for k:=0 to ListOfTables.count-1 do
if pos(searchString,Tstringlist(ListOfTables.objexts[k]).text)>0
then found
To check if a searchString is present in the table with name TableName:
function checkPresent(searchString,targetTable : string; tables :
Tstringlist) : boolean;
var indx : integer;
begin
indx:=tables.IndexOf(targetTable);
result:=(indx>=0) AND Tstringlist(tables[indx]).IndexOf(searchString)>=0)
end;
You can also make the table name a property of a descendant of Tstringlist:
type
Ttable = class(Tstringlist)
tableName : string;
end;
In that case you can then store the Ttables in a Tlist.
Hope I am closer now.
Tom
|
|
| Back to top |
|
|
VBDis
Guest
|
| Posted: Sun Jan 30, 2005 2:38 am Post subject: Re: Referencing a stringlist by name |
|
|
Im Artikel <68clv0d3v5qcdl7ia46icssi55g024rifq (AT) 4ax (DOT) com>, Mark Shapiro
<infocus (AT) swbell (DOT) net> schreibt:
| Quote: | I have the name of the StringList variable as a string. How do I cast
it or otherwise reference it to achieve the functionality of the code
above?
|
Put your stringlists in another stringlist, together with their names. Then
search that stringlist for the stringlist name, obtain the according stringlist
object, and search it for the string as already outlined.
DoDi
|
|
| Back to top |
|
|
AlanGLLoyd
Guest
|
| Posted: Sun Jan 30, 2005 9:26 am Post subject: Re: Referencing a stringlist by name |
|
|
In article <5dmkv05bpdi3u25co0p979uglqssh83r5l (AT) 4ax (DOT) com>, Mark Shapiro
<infocus (AT) swbell (DOT) net> writes:
| Quote: | I would like to create a generic test routine that checks whether or
not any of a series of TStringLists contains any text. How can I
duplicate the following type of functionality for a TStringList?
|
The name of a control or other object is a design-time convenience. It is not
available at run-time unless (again for convenience) the object has a field
called Name in which the design-time string is stored.
Use the reference to the object. Or if you _must_ have design-time names
accessible at run-time make a descendant of TStringList which has a Name
property in which you place the name in your code when it is created.
Or do as DoDi recommends ...
LookUpSL.AddObject('MySLName', MySLName); // add for every stringlist
FindSL := TStringList(LookUpSL.Objects[LookUpSL.IndexOf('MySLName')]);
if FindSL.Text = '' then
Result := false;
Alan Lloyd
[email]alanglloyd (AT) aol (DOT) com[/email]
|
|
| Back to top |
|
|
Bruce Roberts
Guest
|
| Posted: Mon Jan 31, 2005 7:27 pm Post subject: Re: Referencing a stringlist by name |
|
|
"Mark Shapiro" <infocus (AT) swbell (DOT) net> wrote
| Quote: | I would like to create a generic test routine that checks whether or
not any of a series of TStringLists contains any text. How can I
duplicate the following type of functionality for a TStringList? At
runtime, the name of the list will be contained in the CTable
"control_name" field.
if (FindComponent(CTable.FieldByName('control_namel').asString) as
TRichEdit).Text = '' then
Result := false;
|
function EmptyStrings (sl : tStrings) : boolean;
begin
result := sl = '';
end;
Is a generic tStrings test. If you really need a data driven tStrings check
you might want to take a look at the routines in TypInfo. Depending on where
your lists are declared, you may be able to use something there.
OT. I have to say that wanting to do this smells to me of poor design
choice. While there are many exceptions, I've generally found that writing
truly generic application code an exceedingly expensive, total waste of
effort.
If you need string lists that have to alter their behavior when they are
empty, write and use a tStringList descendant instead.
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
