how to get two different file with this procedure in deplhi - delphi

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.

Related

How to effectively check if a string contains one of a few sub strings?

How can I effectively check if a string contains one of a few sub strings?
Suppose I have a string:
`Hi there, <B>my</B> name is Joe <DIV>.</DIV> Hello world. `
How can I check if the string contains either <B> OR <DIV> OR ?
I could do a simple:
Result := (Pos('<B>', S) > 0) or
(Pos('<DIV>', S) > 0) or
(Pos(' ', S) > 0);
But this seems to be very inefficient since it make N (at worst) passes and my strings are considerably large.
Slightly better version:
function StringContainsAny(const S: string; const AnyOf: array of string): Boolean;
var
CurrChr, C: PChar;
i, j, Ln: Integer;
begin
for i := 1 to Length(S) do
begin
CurrChr := #S[i];
for j := 0 to High(AnyOf) do
begin
C := #AnyOf[j][1]; // assume that no empty strings
if C^ <> CurrChr^ then
Continue;
Ln := Length(AnyOf[j]);
if (Length(S) + 1 - i) < Ln then // check bounds
Continue;
if CompareMem(C, CurrChr, Ln * SizeOf(C^)) then
Exit(True);
end;
end;
Exit(False);
end;
You can also build some table of stop-symbols and improve speed. It's kinda complex topic, so I can just suggest you to read, for example, book Bill Smyth "Computing Patterns in Strings".
Here is my solution, thanks to David Heffernan comment:
function StringContainsAny(const S: string; const AnyOf: array of string): Boolean;
var
CurrChr, C: PChar;
I, L, H: Integer;
begin
Result := False;
CurrChr := PChar(S);
while CurrChr^ <> #0 do
begin
H := High(AnyOf);
for I := 0 to H do
begin
L := 0;
C := PChar(AnyOf[I]);
while C^ <> #0 do
begin
if C^ = CurrChr^ then
Inc(L)
else
Break;
Inc(C);
Inc(CurrChr);
if CurrChr^ = #0 then // end of S string
begin
Result := (C^ = #0);
if Result or (not Result and (I = H)) then // match or last AnyOf
Exit;
end;
end;
if C^ = #0 then // match
begin
Result := True;
Exit;
end
else
Dec(CurrChr, L);
end;
Inc(CurrChr);
end;
end;
I'm not sure it is perfect.
EDIT:
What can I say? You know what they say about assumptions...
after actually testing, it seems like using Pos():
function StringContainsAny(const S: string; const AnyOf: array of string): Boolean;
var
I: Integer;
begin
for I := 0 to High(AnyOf) do
begin
if Pos(AnyOf[I], S) <> 0 then
begin
Result := True;
Exit;
end;
end;
Result := False;
end;
Is faster than my solution and #Green_Wizard solution! they did a good job with the Pos function!

Function to increment filename

I'm trying to make a function that can increment a filename.
If last char of the string is a number then increment it.
If last char is a letter then add _1 or _2 or _3(increment this also).
I have to be sure the filename is unique but i cannot use datetime inside filename because all the filenames must be <32 chars without extension.
EX: Apple_99.txt =>Apple_100
Ex: Apple_173 => Apple_174
EX: This_is_my_first_text.txt => This_is_my_first_text_1.txt
Ex: This_is_my_first_text_9.txt => This_is_my_first_text_10.txt
I need to use this in order to rename a file an then upload it to a ftp server.
I've found a function that can do something like this but it only works if the filename contains only uppercase.How can I modify this function in order to access lowercase an uppercase string?
Here is the function:
function IncStr(Str: String; Amount: Integer; Index: Integer = -1): String;
const
MIN_VAL = 65; // 'A'
MAX_VAL = 90; // 'Z'
var
Digit, ToAdd, ToCarry: Integer;
begin
if (Index = 0) and (Amount > 0) then
begin
Result := Char(MIN_VAL + Amount - 1) + Str;
Exit;
end;
if Index = -1 then Index := Length(Str);
ToCarry := 0;
Digit := Ord(Str[Index]);
while not (Digit in [MIN_VAL..MAX_VAL]) do
begin
Dec(Index);
Digit := Ord(Str[Index]);
end;
ToAdd := Digit + Amount;
while (ToAdd > MAX_VAL) do
begin
Dec(ToAdd, 26);
Inc(ToCarry);
end;
Result := Str;
Result[Index] := Char(ToAdd);
if (ToCarry > 0) then
Result := IncStr(Result, ToCarry, Index - 1);
end;
procedure TForm1.Button1Click(Sender: TObject);
var
S: String; // holds string to increment
C: Integer; // amount to increment by
begin
// make sure that Edit1 starts with a valid character
// i.e. 'A' to 'Z'
S := Edit1.Text;
C := StrtoIntDef(Edit2.Text, 0);
// test it, place result in Edit3
Edit3.Text := IncStr(S, C);
{
Example data:
Edit1 := AAZ
Edit2 := 2
= Edit3 := ABB
Edit1 := BZY
Edit2 := 3
= Edit3 := CAB
Edit1 := ZZZ
Edit2 := 1
= Edit3 := AAAA
Edit1 := AA-AC
Edit2 := 3
= Edit3 := AA-AF
Edit1 := AA/Z
Edit2 := 5
= Edit3 := AB/E
... etc
Here's one to try too :-)
Edit1 := ZZZ
Edit2 := 264172
}
end;
Thank you!
Like so many programming problems, the key is to break the problem down into small pieces. First of all, let's write a function to decode the original file name into its constituent parts:
procedure DecodeFileName(const Input: string; out Stem, Ext: string; out Number: Integer);
var
P: Integer;
begin
Ext := TPath.GetExtension(Input);
Stem := TPath.GetFileNameWithoutExtension(Input);
Number := 0;
P := Stem.LastIndexOf('_');
if P = -1 then begin
exit;
end;
if TryStrToInt(Stem.Substring(P+1), Number) then begin
Stem := Stem.Substring(0, P);
end;
end;
The following demonstrates how this works:
DecodeFileName('test.txt', Stem, Ext, Number);
Writeln(Stem, ', ', Number, ', ', Ext);
DecodeFileName('test_dd.txt', Stem, Ext, Number);
Writeln(Stem, ', ', Number, ', ', Ext);
DecodeFileName('test_23.txt', Stem, Ext, Number);
Writeln(Stem, ', ', Number, ', ', Ext);
The output is:
test, 0, .txt
test_dd, 0, .txt
test, 23, .txt
So now you can make a new filename like this:
function IncrementedFileName(const FileName: string): string;
var
Stem, Ext: string;
Number: Integer;
begin
DecodeFileName(FileName, Stem, Ext, Number);
Result := Format('%s_%d%s', [Stem, Number+1, Ext]);
end;
And then we can see how that performs:
Writeln(IncrementedFileName('test.txt'));
Writeln(IncrementedFileName('test_dd.txt'));
Writeln(IncrementedFileName('test_23.txt'));
Writeln(IncrementedFileName('test_28'));
The output is:
test_1.txt
test_dd_1.txt
test_24.txt
test_29
If you don't have access to the string helper methods then you can code it like this:
procedure DecodeFileName(const Input: string; out Stem, Ext: string; out Number: Integer);
var
P: Integer;
begin
Ext := TPath.GetExtension(Input);
Stem := TPath.GetFileNameWithoutExtension(Input);
Number := 0;
P := LastDelimiter('_', Stem);
if P = 0 then begin
exit;
end;
if TryStrToInt(Copy(Stem, P+1, MaxInt), Number) then begin
Stem := Copy(Stem, 1, P-1);
end;
end;
I have not executed this final function, so do not be surprised if it has errors.

Faster way to split text in Delphi TStringList

I have an app that needs to do heavy text manipulation in a TStringList. Basically i need to split text by a delimiter ; for instance, if i have a singe line with 1000 chars and this delimiter occurs 3 times in this line, then i need to split it in 3 lines. The delimiter can contain more than one char, it can be a tag like '[test]' for example.
I've wrote two functions to do this task with 2 different approaches, but both are slow in big amounts of text (more then 2mbytes usually).
How can i achieve this goal in a faster way ?
Here are both functions, both receive 2 paramaters : 'lines' which is the original tstringlist and 'q' which is the delimiter.
function splitlines(lines : tstringlist; q: string) : integer;
var
s, aux, ant : string;
i,j : integer;
flag : boolean;
m2 : tstringlist;
begin
try
m2 := tstringlist.create;
m2.BeginUpdate;
result := 0;
for i := 0 to lines.count-1 do
begin
s := lines[i];
for j := 1 to length(s) do
begin
flag := lowercase(copy(s,j,length(q))) = lowercase(q);
if flag then
begin
inc(result);
m2.add(aux);
aux := s[j];
end
else
aux := aux + s[j];
end;
m2.add(aux);
aux := '';
end;
m2.EndUpdate;
lines.text := m2.text;
finally
m2.free;
end;
end;
function splitLines2(lines : tstringlist; q: string) : integer;
var
aux, p : string;
i : integer;
flag : boolean;
begin
//maux1 and maux2 are already instanced in the parent class
try
maux2.text := lines.text;
p := '';
i := 0;
flag := false;
maux1.BeginUpdate;
maux2.BeginUpdate;
while (pos(lowercase(q),lowercase(maux2.text)) > 0) and (i < 5000) do
begin
flag := true;
aux := p+copy(maux2.text,1,pos(lowercase(q),lowercase(maux2.text))-1);
maux1.add(aux);
maux2.text := copy(maux2.text,pos(lowercase(q),lowercase(maux2.text)),length(maux2.text));
p := copy(maux2.text,1,1);
maux2.text := copy(maux2.text,2,length(maux2.text));
inc(i);
end;
finally
result := i;
maux1.EndUpdate;
maux2.EndUpdate;
if flag then
begin
maux1.add(p+maux2.text);
lines.text := maux1.text;
end;
end;
end;
I've not tested the speed, but for academic purposes, here's an easy way to split the strings:
myStringList.Text :=
StringReplace(myStringList.Text, myDelimiter, #13#10, [rfReplaceAll]);
// Use [rfReplaceAll, rfIgnoreCase] if you want to ignore case
When you set the Text property of TStringList, it parses on new lines and splits there, so converting to a string, replacing the delimiter with new lines, then assigning it back to the Text property works.
The problems with your code (at least second approach) are
You are constantly using lowecase which is slow if called so many times
If I saw correctly you are copying the whole remaining text back to the original source. This is sure to be extra slow for large strings (eg files)
I have a tokenizer in my library. Its not the fastest or best but it should do (you can get it from Cromis Library, just use the units Cromis.StringUtils and Cromis.Unicode):
type
TTokens = array of ustring;
TTextTokenizer = class
private
FTokens: TTokens;
FDelimiters: array of ustring;
public
constructor Create;
procedure Tokenize(const Text: ustring);
procedure AddDelimiters(const Delimiters: array of ustring);
property Tokens: TTokens read FTokens;
end;
{ TTextTokenizer }
procedure TTextTokenizer.AddDelimiters(const Delimiters: array of ustring);
var
I: Integer;
begin
if Length(Delimiters) > 0 then
begin
SetLength(FDelimiters, Length(Delimiters));
for I := 0 to Length(Delimiters) - 1 do
FDelimiters[I] := Delimiters[I];
end;
end;
constructor TTextTokenizer.Create;
begin
SetLength(FTokens, 0);
SetLength(FDelimiters, 0);
end;
procedure TTextTokenizer.Tokenize(const Text: ustring);
var
I, K: Integer;
Counter: Integer;
NewToken: ustring;
Position: Integer;
CurrToken: ustring;
begin
SetLength(FTokens, 100);
CurrToken := '';
Counter := 0;
for I := 1 to Length(Text) do
begin
CurrToken := CurrToken + Text[I];
for K := 0 to Length(FDelimiters) - 1 do
begin
Position := Pos(FDelimiters[K], CurrToken);
if Position > 0 then
begin
NewToken := Copy(CurrToken, 1, Position - 1);
if NewToken <> '' then
begin
if Counter > Length(FTokens) then
SetLength(FTokens, Length(FTokens) * 2);
FTokens[Counter] := Trim(NewToken);
Inc(Counter)
end;
CurrToken := '';
end;
end;
end;
if CurrToken <> '' then
begin
if Counter > Length(FTokens) then
SetLength(FTokens, Length(FTokens) * 2);
FTokens[Counter] := Trim(CurrToken);
Inc(Counter)
end;
SetLength(FTokens, Counter);
end;
How about just using StrTokens from the JCL library
procedure StrTokens(const S: string; const List: TStrings);
It's open source
http://sourceforge.net/projects/jcl/
As an additional option, you can use regular expressions. Recent versions of Delphi (XE4 and XE5) come with built in regular expression support; older versions can find a free regex library download (zip file) at Regular-Expressions.info.
For the built-in regex support (uses the generic TArray<string>):
var
RegexObj: TRegEx;
SplitArray: TArray<string>;
begin
SplitArray := nil;
try
RegexObj := TRegEx.Create('\[test\]'); // Your sample expression. Replace with q
SplitArray := RegexObj.Split(Lines, 0);
except
on E: ERegularExpressionError do begin
// Syntax error in the regular expression
end;
end;
// Use SplitArray
end;
For using TPerlRegEx in earlier Delphi versions:
var
Regex: TPerlRegEx;
m2: TStringList;
begin
m2 := TStringList.Create;
try
Regex := TPerlRegEx.Create;
try
Regex.RegEx := '\[test\]'; // Using your sample expression - replace with q
Regex.Options := [];
Regex.State := [preNotEmpty];
Regex.Subject := Lines.Text;
Regex.SplitCapture(m2, 0);
finally
Regex.Free;
end;
// Work with m2
finally
m2.Free;
end;
end;
(For those unaware, the \ in the sample expression used are because the [] characters are meaningful in regular expressions and need to be escaped to be used in the regular expression text. Typically, they're not required in the text.)

Delphi/pascal Parse a string to a combobox

I'm trying to parse a string (sys) that looks exactly like this
-1|low
0|normal
1|high
I need to pair them in a combo box, where for example, low is the caption and -1 will be the value. What is the best way to do this? What I have so far is:
var
sys : String;
InputLine : TStringList;
InputLine := TStringList.Create;
InputLine.Delimiter := '|';
InputLine.DelimitedText := sys;
Combobox1.items.AddStrings(InputLine);
FreeAndNil(InputLine)
This gives each line of the combo box as such:
-1
low
0
normal
1
high
Parse it manually yourself.
var
SL: TStringList;
StrVal: string;
IntVal: Integer;
Line: string;
DividerPos: Integer;
begin
SL := TStringList.Create;
try
SL.LoadFromFile('Whatever.txt');
for Line in SL do
begin
DividerPos := Pos('|', Line);
if DividerPos > 0 then
begin
StrVal := Copy(Line, DividerPos + 1, Length(Line));
IntVal := StrToInt(Copy(Line, 1, DividerPos - 1));
ComboBox1.Items.AddObject(StrVal, TObject(IntVal));
end;
end
finally
SL.Free;
end;
end;
To retrieve the value from a selected item:
if (ComboBox1.ItemIndex <> -1) then
SelVal := Integer(ComboBox1.Items.Objects[ComboBox1.ItemIndex]);

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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