CODEWITHSUNDEEP
variablesdelphiwith-statementdeclare
Emrah Özmen
Emrah Özmen

Reputation: 31

Create object in 'with' statement without using a variable

var 
  UserName, NickName, UserID: string;
begin
  with TStringList.Create do
  begin
    CommaText := 'ali,veli,4950';
    UserName := x[0];  //what is x ? (x is Tstringlist.create)
    NickName := x[1];
    UserID := x[2];
  end;   
end;

If I use the below code, it works. But I don't want to declare a variable. Can I use it with any variable?

In the with statement, how can I use it?

var 
  tsl: TStringList;
begin
  tsl := TStringlist.Create;
  with tsl do
  begin
    CommaText := 'ali,veli,4950';
    UserName := tsl[0]; 
    NickName := tsl[1];
    UserID := tsl[2];
  end;
end;

Upvotes: 2

Views: 251

Answers (1)

Remy Lebeau
Remy Lebeau

Reputation: 595712

When an object is created directly in a with statement, there is no syntax to refer to that object (unless it provides a member that refers to itself, which is very rare), so you typically must use a variable, as your bottom code does.

Also, both codes are leaking the TStringList object, as you are not calling Free() on it when you are done using it.

That being said, in this particular example, the [] operator is just shorthand for accessing the TStrings.Strings[] default property, which you can access without needing a variable to the created TStringList object, just like you are doing with the TStrings.CommaText property, eg:

var 
  UserName, NickName, UserID: string;
Begin
  with TStringList.Create do
  try
    CommaText := 'ali,veli,4950';
    UserName := Strings[0];
    NickName := Strings[1];
    UserID := Strings[2];
  finally
    Free;
  end;
end;

Upvotes: 7

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