Search numbers in different Memos and separate them into one - delphi

I'm having trouble searching for strings in different memos and separating them.
Let's go to the scene.
in Memo1 i have the following text
18049,25047,text4
18047,25046,text2
18048,25045,text3
18050,25048,text5
18046,25044,text1
and in Memo2
25049,9012646205,55315135004,adou4
25047,"",06252782912,textasidh
25046,"",44425660030,textblabla
25048,"",07649186806,textaldj
I need to separate the first digits up to the comma of memo2 and fetch into memo1 and add the complete lines. Memo1 + Memo2 in Memo3.
18046,25044,text1 25046,"",44425660030,textblabla
18047,25046,text2 25047,"",06252782912,textasidh
18048,25045,text3 25048,"",07649186806,textaldj
18049,25047,text4 25049,9012646205,55315135004,adou4
I've already tried using the function Split(Text, Delimitador: string): TSarray; but without success
var
I, J: Byte;
Z : String;
begin
for I := 1 to 2 do
begin
for J := 0 to TMemo(FindComponent('Memo'+IntToStr(I))).Lines.Count -1 do
begin
Z := Memo2.Lines[J];
if Pos(Split(Z, ',')[0],TMemo(FindComponent('Memo'+IntToStr(I))).Lines[J]) > 0 then
Memo3.Lines.Add(TMemo(FindComponent('Memo'+IntToStr(I))).Lines[J]);
end;
end;
end;

solved
var
I, J : byte;
begin
for I := 0 to Memo1.Lines.Count -1 do
begin
for J := 0 to Memo2.Lines.Count -1 do
begin
if Pos(Split(Memo2.Lines[J], ',')[0],Memo1.Lines[I]) > 0 then
Memo3.Lines.Add(Memo1.Lines[I]+' # '+Memo2.Lines[J]);
end;
end;
end;

Related

How to determine which number occurs most often in an array?

How do I determine which value occurs the most after I filled the array with 100 random values which are between 1 and 11?
Here is a sample code:
procedure TForm1.Button1Click(Sender: TObject);
function Calculate: Integer;
var
Numbers: array [1..100] of Byte;
Counts: array [1..11] of Byte;
I: Byte;
begin
// Fill the array with random numbers
for I := Low(Numbers) to High(Numbers) do
Numbers[I] := Random(11) + 1;
// Count the occurencies
ZeroMemory(#Counts, SizeOf(Counts));
for I := Low(Numbers) to High(Numbers) do
Inc(Counts[Numbers[I]]);
// Identify the maximum
Result := Low(Counts);
for I := Low(Counts) + 1 to High(Counts) do
if Counts[I] > Counts[Result] then
Result := I;
end;
begin
ShowMessage(Calculate.ToString);
end;
It is a simple question [...]
Yes
but I can't seem to find any straight answers online.
You shouldn't be searching for solutions on-line; instead, you should start to think about how to design an algorithm able to solve the problem. For this, you may need pen and paper.
First, we need some data to work with:
const
ListLength = 100;
MinValue = 1;
MaxValue = 11;
function MakeRandomList: TArray<Integer>;
begin
SetLength(Result, ListLength);
for var i := 0 to High(Result) do
Result[i] := MinValue + Random(MaxValue - MinValue + 1);
end;
The MakeRandomList function creates a dynamic array of integers. The array contains ListLength = 100 integers ranging from MinValue = 1 to MaxValue = 11, as desired.
Now, given such a list of integers,
var L := MakeRandomList;
how do we find the most frequent value?
Well, if we were to solve this problem without a computer, using only pen and paper, we would probably count the number of times each distinct value (1, 2, ..., 11) occurs in the list, no?
Then we would only need to find the value with the greatest frequency.
For instance, given the data
2, 5, 1, 10, 1, 5, 2, 7, 8, 5
we would count to find the frequencies
X Freq
2 2
5 3
1 2
10 1
7 1
8 1
Then we read the table from the top line to the bottom line to find the row with the greatest frequency, constantly keeping track of the current winner.
Now that we know how to solve the problem, it is trivial to write a piece of code that performs this algorithm:
procedure FindMostFrequentValue(const AList: TArray<Integer>);
type
TValueAndFreq = record
Value: Integer;
Freq: Integer;
end;
var
Frequencies: TArray<TValueAndFreq>;
begin
if Length(AList) = 0 then
raise Exception.Create('List is empty.');
SetLength(Frequencies, MaxValue - MinValue + 1);
// Step 0: Label the frequency list items
for var i := 0 to High(Frequencies) do
Frequencies[i].Value := i + MinValue;
// Step 1: Obtain the frequencies
for var i := 0 to High(AList) do
begin
if not InRange(AList[i], MinValue, MaxValue) then
raise Exception.CreateFmt('Value out of range: %d', [AList[i]]);
Inc(Frequencies[AList[i] - MinValue].Freq);
end;
// Step 2: Find the winner
var Winner: TValueAndFreq;
Winner.Value := 0;
Winner.Freq := 0;
for var i := 0 to High(Frequencies) do
if Frequencies[i].Freq > Winner.Freq then
Winner := Frequencies[i];
ShowMessageFmt('The most frequent value is %d with a count of %d.',
[Winner.Value, Winner.Freq]);
end;
Delphi has a TDictionary class, which you can use to implement a frequency map, eg:
uses
..., System.Generics.Collections;
function MostFrequent(Arr: array of Integer) : Integer;
var
Frequencies: TDictionary<Integer, Integer>;
I, Freq, MaxFreq: Integer;
Elem: TPair<Integer, Integer>;
begin
Frequencies := TDictionary<Integer, Integer>.Create;
// Fill the dictionary with numbers
for I := Low(Arr) to High(Arr) do begin
if not Frequencies.TryGetValue(Arr[I], Freq) then Freq := 0;
Frequencies.AddOrSetValue(Arr[I], Freq + 1);
end;
// Identify the maximum
Result := 0;
MaxFreq := 0;
for Elem in Frequencies do begin
if Elem.Value > MaxFreq then begin
MaxFreq := Elem.Value;
Result := Elem.Key;
end;
end;
Frequencies.Free;
end;
var
Numbers: array [1..100] of Integer;
I: Integer;
begin
// Fill the array with random numbers
for I := Low(Numbers) to High(Numbers) do
Numbers[I] := Random(11) + 1;
// Identify the maximum
ShowMessage(IntToStr(MostFrequent(Numbers)));
end;
I am also still learning and therefore feel that the way I approached this problem might be a little closer to the way would have done:
procedure TForm1.GetMostOccuring;
var
arrNumbers : array[1..100] of Integer;
iNumberWithMost : Integer;
iNewAmount, iMostAmount : Integer;
I, J : Integer;
begin
for I := 1 to 100 do
arrNumbers[I] := Random(10) + 1;
iMostAmount := 0;
for I := 1 to 10 do
begin
iNewAmount := 0;
for J := 1 to 100 do
if I = arrNumbers[J] then
inc(iNewAmount);
if iNewAmount > iMostAmount then
begin
iMostAmount := iNewAmount;
iNumberWithMost := I;
end;
end;
ShowMessage(IntToStr(iNumberWithMost));
end;
I hope this is not completely useless.
It is just a simple answer to a simple question.

Reverse strings in an array

procedure ReverseArray(var A : array of string);
var I,J,L : integer;
begin
for I := Low(A) to High(A) do
begin
L := length(A[I]);
for J := L downto 1 do M := M + A[I];
end;
writeln(M);
end;
begin
for I := 1 to 4 do readln(T[I]);
ReverseArray(T);
sleep(40000);
end.
What I'm trying to do here basically is reverse every string in the array but I'm unable to do it , what the code above do is basically repeat the words depends on their length (I write 'bob' in the array , the procedure will give me 'bob' three times because the length is 3) ... not sure why it's not working properly and what I'm missing
Delphi has a ReverseString() function in the StrUtils unit.
uses
StrUtils;
type
TStrArray = array of string;
procedure ReverseArray(var A : TStrArray);
var
I: integer;
begin
for I := Low(A) to High(A) do
A[I] := ReverseString(A[I]);
end;
var
T: TStrArray;
I: Integer
begin
SetLength(T, 4);
for I := 1 to 4 do Readln(T[I]);
ReverseArray(T);
...
end.
A string is an array of char with some extra bells and whistles added.
So an array of string is a lot like an array of array of char.
If you want to reverse the string, you'll have to access every char and reverse it.
procedure ReverseArray(var A : array of string);
var
i,j,Len : integer;
B: string;
begin
for i := Low(A) to High(A) do begin
Len := length(A[i]);
SetLength(B, Len); //Make B the same length as A[i].
//B[Len] = A[i][1]; B[Len-1]:= A[i][2] etc...
for j := Len downto 1 do B[j]:= A[i][(Len-J)+1];
//Store the reversed string back in the array.
A[i]:= B;
//Because A is a var parameter it will be returned.
//Writeln(B); //Write B for debugging purposes.
end;
end;
var
i: integer;
Strings: array [0..3] of string;
begin
for i := 0 to 3 do readln(Strings[i]);
ReverseArray(Strings);
for i := 0 to 3 do writeln(Strings[i]);
WriteLn('Done, press a key...');
ReadLn;
end.
Some tips:
Do not use global variables like M but declare a local variable instead.
Don't do AStr:= AStr + AChar in a loop, if you can avoid it. If you know how long the result is going to be use the SetLength trick as shown in the code. It's generates much faster code.
Instead of a Sleep you can use a ReadLn to halt a console app. It will continue as soon as you press a key.
Don't put the writeln in your working routine.
Note the first element in a string is 1, but the first element in a array is 0 (unless otherwise defined); Dynamic arrays always start counting from zero.
Note that array of string in a parameter definition is an open array; a different thing from a dynamic array.
Single uppercase identifiers like T, K, etc are usually used for generic types, you shouldn't use them for normal variables; Use a descriptive name instead.
Come on! 'bob' is one of those words you shouldn't try to test a reverse routine. But the problem goes beyond that.
Your problem is in here
for J := L downto 1 do
M := M + A[I];
You are trying to add the whole string to the M variable instead of the character you are trying to access. So, it should be
for J := L downto 1 do
M := M + A[I][J];
Also you need to set M := '' inside the first loop where it will have nothing when you start accumulating characters in to it.
Third, move the writing part, WriteLn(M), inside the first loop where you get a nice, separated outputs.
Putting together, it is going to be:
for I := Low(A) to High(A) do
begin
L := length(A[I]);
M := '';
for J := L downto 1 do
M := M + A[I][J];
writeln(M);
end;
My preferred solution for this is
type
TStringModifier = function(const s: string): string;
procedure ModifyEachOf( var aValues: array of string; aModifier: TStringModifier );
var
lIdx: Integer;
begin
for lIdx := Low(aValues) to High(aValues) do
aValues[lIdx] := aModifier( aValues[lIdx] );
end;
and it ends up with
var
MyStrings: array[1..3] of string;
begin
MyStrings[1] := '123';
MyStrings[2] := '456';
MyStrings[3] := '789';
ModifyEachOf( MyStrings, SysUtils.ReverseString );
end;
uses
System.SysUtils, System.StrUtils;
var
Forwards, backwards : string;
begin
forwards:= 'abcd';
backwards:= ReverseString(forwards);
Writeln(backwards);
Readln;
end;
// dcba

How do I load a chess board into program once saved?

I have a procedure that saves a chess board into a text file. I am trying to read the board back in to the program once saved. When I call this procedure I get this error.
Code which I have for loading in board.
Procedure LoadBoard(Var Board : Tboard);
var
fptr:text;
i,j,x:integer;
line:string;
load:char;
begin
Write('Do you want a load a game? (Enter Y for yes)');
Readln(load);
If (Ord(load) >= 97) and (Ord(load) <= 122)
Then load := Chr(Ord(load) - 32);
if load='Y' then
begin
assignfile(fptr,'SBoard.txt');
reset(fptr);
i:=1;
repeat
readln(fptr,line);
j:=1;
x:=1;
repeat
begin
if (line[x]<>',') and (line[x+1]<>',')
then
begin
Board[i,j][1]:=line[x];
Board[i,j][2]:=line[x+1];
end;
if line[x]=','
then
j:=j+1;
x:=x+1;
end;
until j=9;
i:=i+1;
until i=9;
close(fptr);
end;
end;
You get the Access Violation exception because the string members in your Board array are empty (length is zero) and therefore have no accessible character positions.
To fix your present code, you should use SetLength() on each string member before you assign content to the character positions. You have not shown what the strings contain, so only you know what the set length should be.
On the other hand, in previous answer to your questions you have been adviced several other methods to save your chess board. You should review those and possibly choose one of them. It would also be polite to respond to those answers and maybe tell why you did not select them. Maybe we were not able to explain the benefits.
You are over complicating things by using a Text file and saving your board line by line.
I think you should use a TStringList for saving and loading :
Const
BoardDimension = 8;
BoardFileName = 'SBoard.txt';
Type
TBoard = Array [1 .. BoardDimension, 1 .. BoardDimension] Of String;
procedure SaveBoard(Board: TBoard);
var
i, j: Integer;
Line, BoardFile: TStringList;
begin
BoardFile := TStringList.Create;
Line := TStringList.Create;
for i := 1 to BoardDimension do
begin
Line.Clear;
for j := 1 to BoardDimension do
Line.Add(Board[i, j]);
BoardFile.Add(Line.CommaText);
end;
Line.Free;
BoardFile.SaveToFile(BoardFileName);
BoardFile.Free;
end;
procedure LoadBoard(Board: TBoard);
var
i, j: Integer;
Line, BoardFile: TStringList;
begin
if not FileExists(BoardFileName) then
exit; // Show error message
BoardFile := TStringList.Create;
BoardFile.LoadFromFile(BoardFileName);
Line := TStringList.Create;
for i := 1 to BoardDimension do
begin
Line.CommaText := BoardFile[i];
for j := 1 to BoardDimension do
Board[i, j] := Line[j];
end;
Line.Free;
BoardFile.Free;
end;
And if you want to test the load an save proceudre you could do it like this :
procedure Test;
var
Board: TBoard;
BoardA: TBoard;
i, j: Integer;
begin
randomize;
for i := 1 to BoardDimension do
for j := 1 to BoardDimension do
Board[i, j] := Random(500).ToString;
SaveBoard(Board); //Save Board
LoadBoard(BoardA); //Load the file into a NEW board
for i := 1 to BoardDimension do //Comapre the two boards
for j := 1 to BoardDimension do
if Board[i,j] <> BoardA[i,j] then
raise Exception.Create('Wrong file format');
end;

how to get two different file with this procedure in deplhi

i want to get value from two file .txt, one file contain different dimension matrix with other
i have try this code:
procedure TfrmJST.ParseDelimited(const S1: TStrings; const Value: String; const Delimiter: String);
var
dx,cx: integer;
ns,ms: String;
txt: string;
delta,teta: integer;
procedure TfrmJST.ParseDelimited(const S1: TStrings; const Value: String; const Delimiter: String);
var
dx,cx: integer;
ns,ms: String;
txt: string;
delta,teta: integer;
begin
Col := 1;
Delta := Length(Delimiter);
Txt := Value+Delimiter;;
begin
while Length(Txt) > 1 do
begin
Dx := Pos(Delimiter, Txt);
Ns := Trim(Copy(Txt, 1, Dx-1));
// S1.Add('#'+Ns+'*'); //only needed for testing
if Ns <> '' then
begin
Matrix[Row,Col] := StrToFloat(Ns); //for first matrix
Inc(Col);
end;
Txt := Copy(Txt, Dx+Delta, MaxInt);
end;
end;
Col := 1;
teta := Length(delimiter);
txt := value+delimiter;
begin
while Length(txt) > 1 do
begin
cx := Pos(delimiter, txt);
ms := Copy(txt, 1, cx-1);
if ms <> '' then
begin
ref[Row,Col] := StrToFloat(ms); ///for 2nd matrix
Inc(Col);
end;
txt := Copy(txt, cx+teta, MaxInt);
end;
end;
end;
and this is initialize of matrix:
private
{ Private declarations }
Row, Col: integer;
Matrix: array[1..140,1..141] of double;
Ref: array[1..2,1..140] of double ;
this is the implementation:
begin
Temp := TStringList.Create;
MemoSL:= TStringList.Create ;
Temp.LoadFromFile('trainer.txt');
Row := 1;
for I := 0 to Temp.Count-1 do
begin
ParseDelimited(MemoSL, Trim(Temp.Strings[I]), ' ');
Inc(Row); //stackoverflow error in this line
end;
Temp.Free;
//parsing second matrix
TempList := TStringList.Create;
Templist.LoadFromFile('refbaru.txt');
row := 1;
for J := 0 to Templist.Count-1 do
begin
T := Templist[J];
ParseDelimited(Memo1.Lines, T, ' ');
Inc(row);
end;
Templist.Free;
i tried that code but give me error,
the error was stackoverflow error in line 'inc(row)' that process first matrix.
and while i gave comment out at the second function that process 2nd matrix, Temp[i] only returns 2 rows of matrix[140x141]. does it mean the code can't process two different file? and why it only return two rows of the matrix?
anyone can help me?
while Length(Txt) > 1 do
begin
Dx := Pos(Delimiter, Txt);
Ns := Trim(Copy(Txt, 1, Dx-1));
// S1.Add('#'+Ns+'*'); //only needed for testing
if Ns <> '' then
begin
Matrix[Row,Col] := StrToFloat(Ns); //for first matrix
Inc(Col);
end;
Txt := Copy(Txt, Dx+Delta, MaxInt);
end;
Looking at this piece of code I see the posibility of an endless loop: what happens if there is no Delimiter found? It will keep running and forever increase your 'col' value. Make sure to have a condition to stop your while loop if no delimeter is found.
It is pointless to look for a specific stack overflow error when many ordinary errors already exist.
If your code is clean programmed and it is still stack overflow, then of course, is time to look deeper into the code.
But first ! As long as you can see obvious errors, you should remove them.
1.) "Row" used in the same procedure on a 140 dimension array and on a only 2 dimension array.
How can that work ?
Matrix: array[1..140,1..141] of double;
Ref: array[1..2,1..140] of double ;
File 'trainer.txt' 140 Lines
File 'refbaru.txt' 2 Lines.
for I := 0 to Temp.Count-1 do // 140 lines
// ParseDelimited() will only run properly if Row < 3
// remember -> Ref: array[1..2,1..140])
// if Row > 2 , with Ref[Row,Col] := , 137 times data is overwritten.
procedure ParseDelimited(MemoSL, Trim(Temp.Strings[I]), ' ');
....
Matrix[Row,Col] := StrToFloat(Ns);
....
Ref[Row,Col] := StrToFloat(ms);
....
end;
Inc(Row);
end;
2.) If you run the second loop with refbaru.txt and the two arrays are present together in the procedure ParseDelimited(), then you overwrite 2 values of array Matrix
recommendation
make sure: Loop through trainer.txt, writes values only to the Matrix array.
make sure: Loop through refbaru.txt, writes values only to the Ref array.
Your code could look something like:
[...]
filetoload: String;
[...]
procedure TfrmJST.ParseDelimited(S1: TStrings; Value: String; const Delimiter: String);
var
f:double;
[...]
Col := 1;
txt := Value+Delimiter;
[...]
if filetoload='trainer.txt' then begin
Delta := Length(Delimiter);
while Length(txt) > 1 do
begin
Dx := Pos(Delimiter, txt);
Ns := Trim(Copy(txt, 1, Dx-1));
if Ns <> '' then
begin
if TryStrToFloat(Ns,f) then Matrix[Row,Col]:=f;
Inc(Col);
if Col > MatrixColMax then break;
txt := Copy(txt, Dx+Delta, MaxInt);
end else txt:='';
end;
end;
if filetoload='refbaru.txt' then begin
teta := Length(delimiter);
while Length(txt) > 1 do
begin
cx := Pos(delimiter, txt);
ms := Copy(txt, 1, cx-1);
if ms <> '' then
begin
if TryStrToFloat(ms,f) then Ref[Row,Col]:=f;
Inc(Col);
if Col > RefColMax then break;
txt := Copy(txt, cx+teta, MaxInt);
end else txt:='';
end;
end;
begin
[...]
filetoload:='trainer.txt';
Temp := TStringList.Create;
Temp.LoadFromFile(filetoload);
if Temp.Count > MatrixRowMax then LinesToLoad:=MatrixRowMax-1 else
LinesToLoad:=Temp.Count-1;
for I := 0 to LinesToLoad do
[...]
ParseDelimited(MemoSL, Trim(Temp.Strings[I]), ' ');
[...]
end;
filetoload:='refbaru.txt';
TempList := TStringList.Create;
TempList.LoadFromFile(filetoload);
if TempList.Count > RefRowMax then LinesToLoad:=RefRowMax-1 else
LinesToLoad:=TempList.Count-1;
for J := 0 to LinesToLoad do
[...]
ParseDelimited(Memo1.Lines, T, ' ');
[...]
end;
end;
You should also compare the linesize of the file with the size of the arrays
RefRowMax: integer;
RefColMax: integer;
MatrixRowMax: integer;
MatrixColMax: integer;
LinesToLoad: integer;
....
RefRowMax:=2;
RefColMax:=140;
MatrixRowMax:=140;
MatrixColMax:=141;
....
procedure ParseDelimited()
if filetoload='trainer.txt' then begin
[...]
Inc(Col)
if Col > MatrixColMax then break;
end;
if filetoload='refbaru.txt' then begin
[...]
Inc(Col)
if Col > RefColMax then break;
end;
You should also look for a valid value of Ns , StrToFloat(Ns) before you write to the arrays in ParseDelimited()
function TryStrToFloat(const S: string; out Value: Double): Boolean;
or
Val();
var
f:double;
....
begin
....
if TryStrToFloat(Ns,f) then Matrix[Row,Col]:=f;
....
The OP overwritting many of used data.
And when he has enough data overwritten, he gets a stack overflow error.

Word blocks in TMemo

I am trying to make a basic Hex viewer out of a TMemo, I know this is probably not ideal but it will be only me personally using it so that does not really matter.
(1)
Firstly, suppose a Memo is filled with Hex information like so:
How could I get a count of all the text blocks shown, ignoring the white space? So using the image the result in this case would be 28.
This is what I tried and I know it is completely wrong as I am accessing the Memo lines but I don't know how to access each character.
I cant seem to solve this simple problem :(
function CountWordBlocks(Memo: TMemo): Integer;
var
i: Integer;
vCount: Integer;
begin
for i := 0 to Memo.Lines.Count - 1 do
begin
if Length(Memo.Lines.Strings[i]) = 2 then
begin
Inc(vCount);
end;
end;
Result := vCount;
end;
Here is the code I am using to display the Hex values in the Memo:
procedure ReadFileAsHex(const AFileName: string; ADestination: TStrings);
var
fs: TFileStream;
buff: Byte;
linecount: Byte;
line: string;
begin
linecount := 0;
line := '';
fs := TFileStream.Create(AFileName, fmOpenRead);
try
ADestination.BeginUpdate;
try
while fs.Position < fs.Size do
begin
fs.Read(buff, 1);
line := line + IntToHex(buff, 2) + ' ';
Inc(linecount);
if linecount = 16 then
begin
ADestination.Add(line);
line := '';
linecount := 0;
end;
end;
if Length(line) <> 0 then
ADestination.Add(line);
finally
ADestination.EndUpdate;
end;
finally
fs.Free;
end;
end;
(2)
If I click onto the Memo and a text block is under the cursor, how could I know which number the selected block is out of all the others?
So using the same first image, the caret is at the top line next to 68, so the result would be 3 as it is the third text block out of 28.
This should be so easy but I cannot think clearly, I don't have the right programming mind yet and so really struggle with basic logic and solving problems!
(3)
Finally I would like to select a block at runtime by passing a block number value. I tried this without much success:
procedure FindBlock(Memo: TMemo; BlockNumber: Integer);
var
i: Integer;
txt: string;
ThisWhite, PrevWhite: boolean;
vRead: Integer;
begin
txt := Memo.Text;
vRead:= 0;
PrevWhite := True;
for i := 1 to Length(txt) do
begin
ThisWhite := Character.IsWhiteSpace(txt[i]);
if PrevWhite and not ThisWhite then
begin
Inc(vRead);
PrevWhite := False;
end;
PrevWhite := ThisWhite;
if vRead = BlockNumber then
begin
Memo.SelStart := vRead;
Memo.SetFocus;
Exit;
end;
end;
end;
(1)
This works:
function TForm1.CountBlocks: integer;
var
i: Integer;
txt: string;
ThisWhite, PrevWhite: boolean;
begin
txt := Memo1.Text;
result:= 0;
PrevWhite := true;
for i := 1 to Length(txt) do
begin
ThisWhite := Character.IsWhiteSpace(txt[i]);
if PrevWhite and not ThisWhite then
begin
inc(result);
PrevWhite := false;
end;
PrevWhite := ThisWhite;
end;
end;
However, it can be optimized if more detailed information about the memo contents is available. For instance, if you know that each line consists of four blocks, then the number of blocks is simply 4*Memo1.Lines.Count. My code above will even accept blocks of different width.
(2)
Simply replace
for i := 1 to Length(txt) do
by
for i := 1 to Memo1.SelStart + 1 do
Since you are in control of the formatting of your lines, and the lines have a fixed format, it is very easy to calculate the number of bytes being displayed without resorting to looping through the individual lines one a time. Every line displays 3 characters per byte, and every line other than the last line displays 16 bytes, thus 48 characters per complete 16-byte line. Use those facts to your advantage to calculate the number of bytes based on the number of complete 16-byte lines present, and then you can add on the number of remaining bytes from just the last line:
function CountWordBlocks(Memo: TMemo): Integer;
var
Count: Integer;
begin
Count := Memo.Lines.Count;
if Count > 0 then
Result := (16 * (Count-1)) + (Length(Memo.Lines[Count-1]) div 3);
else
Result := 0;
end;
You can do something similar to translate a character offset within the Memo into a work block number:
function GetCurrentWordBlock(Memo: TMemo): Integer;
var
SelStart, LineStart, LineNum: Integer
begin
Result := 0;
SelStart := Memo.SelStart;
if SelStart < 0 then Exit;
LineStart := Memo.Perform(EM_LINEINDEX, SelStart, 0);
if LineStart < 0 then Exit;
LineNum := Memo.Perform(EM_LINEFROMCHAR, LineStart, 0);
Result := (16 * LineNum) + ((SelStart - LineStart) div 3) + 1;
end;
To select a given block number, you can do this:
procedure FindBlock(Memo: TMemo; BlockNumber: Integer);
var
LineNum, LineStart: Integer;
begin
if BlockNumber < 1 then Exit;
LineNum = (BlockNumber - 1) div 16;
LineStart = Memo.Perform(EM_LINEINDEX, LineNum, 0);
if LineStart < 0 then Exit;
Memo.SelStart = LineStart + (((BlockNumber - 1) - (16 * LineNum)) * 3);
Memo.SelLength := 2;
Memo.SetFocus;
end;

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