将带逗号的字符串转换为float

Is there a built-in Delphi function which would convert a string such as '3,232.00' to float? StrToFloat raises an exception because of the comma. Or is the only way to strip out the comma first and then do StrToFloat?

是否有内置的Delphi函数可以将诸如'3,232.00'之类的字符串转换为float?由于逗号,StrToFloat引发异常。或者是首先删除逗号然后执行StrToFloat的唯一方法?

Thanks.

9 个解决方案

#1

Do you exactly know, that '.' is decimal separator and ',' is thousand separator (always)? If so, then you should fill the TFormatSettings record and pass it to StrToFloat.

你知道吗,'。'是小数分隔符和','是千位分隔符(总是)?如果是这样,那么你应该填写TFormatSettings记录并将其传递给StrToFloat。

FillChar(FS, SizeOf(FS), 0);
... // filling other fields
FS.ThousandSeparator := ',';
FS.DecimalSeparator := '.';
V := StrToFloat(S, FS);

#2

below is what i use. there might be more efficient ways, but this works for me. in short, no, i don't know of any built-in delphi function that will convert a string-float containing commas to a float

以下是我使用的。可能会有更有效的方法,但这对我有用。简而言之,不,我不知道任何内置的delphi函数会将包含逗号的字符串浮点数转换为浮点数

{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  safeFloat

  Strips many bad characters from a string and returns it as a double.
}
function safeFloat(sStringFloat : AnsiString) : double;
var
  dReturn : double;

begin
  sStringFloat := stringReplace(sStringFloat, '%', '', [rfIgnoreCase, rfReplaceAll]);
  sStringFloat := stringReplace(sStringFloat, '$', '', [rfIgnoreCase, rfReplaceAll]);
  sStringFloat := stringReplace(sStringFloat, ' ', '', [rfIgnoreCase, rfReplaceAll]);
  sStringFloat := stringReplace(sStringFloat, ',', '', [rfIgnoreCase, rfReplaceAll]);
  try
    dReturn := strToFloat(sStringFloat);
  except
    dReturn := 0;
  end;
  result := dReturn;

end;

#3

Try: StrToFloat(StringReplace('3,232.00', ',', '') It should get rid of the commas before doing the conversion.

尝试:StrToFloat(StringReplace('3,232.00',',','')它应该在进行转换之前删除逗号。

In C# / VB.NET I use would use something like decimal.convert("3,232.00", ",", "");

在C#/ VB.NET中,我使用的方法是使用decimal.convert(“3,232.00”,“,”,“”);

I know of no way to do the conversion without stripping out the extra characters. In fact, I have a special function in my library that strips out commas and currency symbols. So a actually call MyConverer.decimalConverter("$3,232.00");

我知道没有办法在不剥离额外字符的情况下进行转换。事实上,我的库中有一个特殊功能,可以删除逗号和货币符号。所以实际上调用MyConverer.decimalConverter(“$ 3,232.00”);

#4

function StrToFloat_Universal( pText : string ): Extended;
const
   EUROPEAN_ST = ',';
   AMERICAN_ST = '.';
var
  lformatSettings : TFormatSettings;
  lFinalValue     : string;
  lAmStDecimalPos : integer;
  lIndx           : Byte;
  lIsAmerican     : Boolean;
  lIsEuropean     : Boolean;

begin
  lIsAmerican := False;
  lIsEuropean := False;
  for lIndx := Length( pText ) - 1 downto 0 do
  begin
    if ( pText[ lIndx ] = AMERICAN_ST ) then
    begin
      lIsAmerican := True;
      pText := StringReplace( pText, ',', '', [ rfIgnoreCase, rfReplaceAll ]);  //get rid of thousand incidental separators
      Break;
    end;
    if ( pText[ lIndx ] = EUROPEAN_ST ) then
    begin
      lIsEuropean := True;
      pText := StringReplace( pText, '.', '', [ rfIgnoreCase, rfReplaceAll ]);  //get rid of thousand incidental separators
      Break;
    end;
  end;
  GetLocaleFormatSettings( LOCALE_SYSTEM_DEFAULT, lformatSettings );
  if ( lformatSettings.DecimalSeparator = EUROPEAN_ST ) then
  begin
    if lIsAmerican then
    begin
      lFinalValue := StringReplace( pText, '.', ',', [ rfIgnoreCase, rfReplaceAll ] );
    end;
  end;
  if ( lformatSettings.DecimalSeparator = AMERICAN_ST ) then
  begin
    if lIsEuropean then
    begin
      lFinalValue := StringReplace( pText, ',', '.', [ rfIgnoreCase, rfReplaceAll ] );
    end;
  end;
  pText  := lFinalValue;
  Result := StrToFloat( pText, lformatSettings );
end;

#5

I use a function which is able to handle the ',' and the '.' as decimalseparator...:

我使用的函数能够处理','和'。'作为decimalpaparator ...:

function ConvertToFloat(aNr: String; aDefault:Integer): Extended;
var
  sNr, s3R, sWhole, sCent:String;
  eRC:Extended;
begin
  sNr:=ReplaceStr(sNr, ' ', '');

  if (Pos('.', sNr) > 0) or (Pos(',', sNr) > 0) then
  begin
    // Get 3rd character from right
    s3R:=LeftStr(RightStr(sNr, 3), 1);
    if s3R <> DecimalSeparator then
    begin
      if not IsNumber(s3R) then
      begin
        s3R := DecimalSeparator;
        sWhole := LeftSr(sNr, Length(sNr) - 3);
        sCent := (RightStr(sNr, 2);
        sNr := sWhole + DecimalSeparator + sCent;
      end
      else
        // there are no decimals... add ',00'
        sNr:=sNr + DecimalSeparator + '00';
    end;
    // DecimalSeparator is present; get rid of other symbols
    if (DecimalSeparator = '.') and (Pos(',', sNr) > 0) then sNr:=ReplaceStr(sNr, ',', '');
    if (DecimalSeparator = ',') and (Pos('.', sNr) > 0) then sNr:=ReplaceStr(sNr, '.', '');
  end;

  eRc := StrToFloat(sNr);
end;

#6

I had the same problem when my Users need to enter 'scientific' values such as "1,234.06mV". Here there is a comma, a multiplier (m=x0.001) and a unit (V). I created a 'wide' format converter routine to handle these situtations. Brian

当我的用户需要输入“科学”值,例如“1,234.06mV”时,我遇到了同样的问题。这里有一个逗号,一个乘数(m = x0.001)和一个单位(V)。我创建了一个'宽'格式转换器例程来处理这些情况。布赖恩

#7

Myfunction:

function StrIsFloat2 (S: string;  out Res: Extended): Boolean;
var
  I, PosDecimal: Integer;
  Ch: Char;
  STrunc: string;
  liDots, liComma, J: Byte;
begin
  Result := False;
  if  S = ''
  then  Exit;
  liDots := 0;
  liComma := 0;
  for  I := 1 to Length(S)  do  begin
    Ch := S[I];
    if  Ch = FormatSettings.DecimalSeparator  then  begin
      Inc (liDots);
      if  liDots > 1  then  begin
        Exit;
      end;
    end
    else if  (Ch = '-') and (I > 1) then  begin
      Exit;
    end
    else if Ch = FormatSettings.ThousandSeparator then begin
      Inc (liComma);
    end
    else if not CharIsCipher(Ch) then  begin
      Exit;
    end;
  end;
  if liComma > 0 then begin
    PosDecimal := Pos (FormatSettings.DecimalSeparator, S);
    if PosDecimal = 0 then
      STrunc := S
    else
      STrunc := Copy (S, 1, PosDecimal-1);
    if STrunc[1] = '-' then
      Delete (S, 1, 1);
    if Length(STrunc) < ((liComma * 3) + 2) then
      Exit;
    J := 0;
    for I := Length(STrunc) downto 1 do begin
      Inc(J);
      if J mod 4 = 0 then
        if STrunc[I] <> FormatSettings.ThousandSeparator then
          Exit;
    end;
    S := ReplaceStr (S, FormatSettings.ThousandSeparator, '');
  end;
  try
    Res := StrToFloat (S);
    Result := True;
  except
    Result := False;
  end;
end;

#8

Using Foreach loop

使用Foreach循环

 public static float[] ToFloatArray()
    {
     string pcords="200.812, 551.154, 232.145, 482.318, 272.497, 511.752";

      float[] spiltfloat = new float[pcords.Split(',').Length];
        int i = 0;
        foreach (string s in pcords.Split(','))
        {
           spiltfloat[i] = (float)(Convert.ToDouble(s));
            i++;
        }
        return spiltfloat;
    }

#9

using lemda Expression to convert string comma seprated to float array

使用lemda Expression将字符串逗号转换为float数组

public static float[] ToFloatArrayUsingLemda()
    {
        string pcords="200.812, 551.154, 232.145, 482.318, 272.497, 511.752";
        float[] spiltfloat = new float[pcords.Split(',').Length];

        string[] str = pcords.Split(',').Select(x => x.Trim()).ToArray();

        spiltfloat = Array.ConvertAll(str, float.Parse);
        return spiltfloat;
    }