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C# string to Decimal On All style or Culture

Hi I want to find if there is any better way to parse the string to Decimal which covers various format
$1.30
£1.50
€2,50
2,50  €
2.500,00  €
I see a lot of examples using culture to convert . & ,. But in my case, I don't have anything to identify the culture.
This display field I get from the client and I need to extract the value.
I tried following (which didn't work for all scenario) but would like to know if we have any best way to handle this.
Decimal.Parse(value,NumberStyles.Currency |
NumberStyles.Number|NumberStyles.AllowThousands |
NumberStyles.AllowTrailingSign | NumberStyles.AllowCurrencySymbol)
I also tried to use Regex to remove the currency sign but unable to convert both 1.8 or 1,8 in one logic.

Well, assuming you always get a valid currency format, and it's only the culture that changes, you could guess which character is used as a decimal point and which is used as a thousands separator by checking which appears the last in the number. Then remove all the thousand separators and parse it like its culture was invariant.
The code would look like the following:
// Replace with your input
var numberString = "2.500,00 €";
// Regex to extract the number part from the string (supports thousands and decimal separators)
// Simple replace of all non numeric and non ',' '.' characters with nothing might suffice as well
// Depends on the input you receive
var regex = new Regex"^[^\\d-]*(-?(?:\\d|(?<=\\d)\\.(?=\\d{3}))+(?:,\\d+)?|-?(?:\\d|(?<=\\d),(?=\\d{3}))+(?:\\.\\d+)?)[^\\d]*$");
char decimalChar;
char thousandsChar;
// Get the numeric part from the string
var numberPart = regex.Match(numberString).Groups[1].Value;
// Try to guess which character is used for decimals and which is used for thousands
if (numberPart.LastIndexOf(',') > numberPart.LastIndexOf('.'))
{
decimalChar = ',';
thousandsChar = '.';
}
else
{
decimalChar = '.';
thousandsChar = ',';
}
// Remove thousands separators as they are not needed for parsing
numberPart = numberPart.Replace(thousandsChar.ToString(), string.Empty);
// Replace decimal separator with the one from InvariantCulture
// This makes sure the decimal parses successfully using InvariantCulture
numberPart = numberPart.Replace(decimalChar.ToString(),
CultureInfo.InvariantCulture.NumberFormat.CurrencyDecimalSeparator);
// Voilá
var result = decimal.Parse(numberPart, NumberStyles.AllowDecimalPoint | NumberStyles.Number, CultureInfo.InvariantCulture);
It does look a bit of complicated for a simple decimal parsing, but I think should do the work for all the input numbers you get or at least the most of them.
If you do this in some sort of loop, you might want to use compiled regex.

The problem here is that in one case . means decimal point but in other it is a thousnads separator. And then you have , as decimal separator. Clearly, it is impossible for the parser to "guess" what is meant, so the only thing you can do is to decide on some rules on how to handle which case.
If you have control over the UI the best approach would be to validate user input and just reject any value that can't be parsed with an explanation on which format is expected.
If you have no control over the UI, the second best option would be to check for some "rules" and then devise which culture is appropriate for that given input and try to run it through decimal.TryParse for that given culture.
For the given input you have, you could have the following rules:
input.StartsWith("$") -> en-US
input.StartsWith("£") -> en-GB
input.StartsWith("€") || input.EndsWith("€") -> de-DE
These could reasonably handle all cases.
In code:
static void Main(string[] args)
{
string[] inputs =
{
"$1.30",
"£1.50",
"€2,50",
"2,50 €",
"2.500,00 €"
};
for (int i = 0; i < inputs.Length; i++)
{
Console.Write((i + 1).ToString() + ". ");
if (decimal.TryParse(inputs[i], NumberStyles.Currency,
GetAppropriateCulture(inputs[i]), out var parsed))
{
Console.WriteLine(parsed);
}
else
{
Console.WriteLine("Can't parse");
}
}
}
private static CultureInfo GetAppropriateCulture(string input)
{
if (input.StartsWith("$"))
return CultureInfo.CreateSpecificCulture("en-US");
if (input.StartsWith("£"))
return CultureInfo.CreateSpecificCulture("en-GB");
if (input.StartsWith("€") || input.EndsWith("€"))
return CultureInfo.CreateSpecificCulture("de-DE");
return CultureInfo.InvariantCulture;
}
Output:
1.30
1.50
2.50
2.50
2500.00

The only way you could do that is just strip string from symbols and change . and , to decimal separator. Something like:
public decimal UniversalConvertDecimal(string str)
{
char currentDecimalSeparator = Convert.ToChar(Thread.CurrentThread.CurrentCulture.NumberFormat.NumberDecimalSeparator);
str = str.Replace('.', currentDecimalSeparator);
str = str.Replace(',', currentDecimalSeparator);
StringBuilder builder = new StringBuilder(str.Length);
foreach(var ch in str)
{
if(Char.IsDigit(ch) || ch == currentDecimalSeparator)
builder.Add(ch);
}
string s = builder.ToString();
return Convert.ToDecimal(s);
}
First you have to get current decimal separator from your system.
Then you have to replace . and , with current decimal separator.
Next, you will have to strip the string from any other char than a digit or decimal separator. At the end you can be sure that Convert.ToDecimal is going to work. But I don't know if it is something you want to achieve.
If you need some mechanism to save currency to database, there is a far simpler solution. Just convert this currency to least currency part. For example instead of $1, save 100 cents.
So if you have $1.99, just multiply it by 100 and you will get: 199 cents. And this integer can be saved to db.

Trim decimal to 2 decimal places except if decimal has more than 2 decimal places

So this is a bit of a picky question. I have looked around for similar questions, but couldn't find one that specifically answers my question.
I'm making a winforms app that gets data from, among other things, numeric updowns and places them in Word docvariables. The numeric updowns have a precision of 4 decimal places, because there are some prices like €0,0125 for example printing contracts. But other prices will get saved as for example €12,5000. I currently fix the numbers with 2 decimal places like this:
string value = type.GetValue().ToString().Trim(new char[] { '\'' });
//Changes commas for European standard and removes the excess zeros after the comma.
if (type.GetType().ToString().EndsWith("Decimal"))
{
string s;
string sep = CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator;
if (sep == ".")
s = double.Parse(value).ToString("n2").Replace('.', ',');
else
s = double.Parse(value).ToString("n2");
wordDoc.Variables[type.GetName()].Value = s;
}
else
wordDoc.Variables[type.GetName()].Value = value;
But I can't seem to figure out how to detect when a decimal shouldn't get trimmed. I don't necessarily need code examples, if someone just could send me on the right track, that would be a major help.
NB: Changing the precision of the numeric up downs isn't really an option since they get created dynamically by a method.

Just use a custom format string - #,##0.00## will show a minimum of 2 d.p. and a maximum of 4 d.p.
decimal x = 12.50000m;
decimal y = 0.0125m;
string sx = x.ToString("#,##0.00##"); // "12.50"
string sy = y.ToString("#,##0.00##"); // "0.125"
If you want a comma decimal separator, then either use an appropriate CultureInfo or create a NumberFormatInfo with the correct properties:
var nfi = new NumberFormatInfo
{
NumberDecimalSeparator = ",",
NumberGroupSeparator = ".",
};
string s = 1234.56m.ToString("#,##0.00##", nfi); // "1.234,56"

How to change 1 to 00001?

I want to have numbers with a fixed digit count.
example: 00001, 00198, 48484
I can do like this:
string value;
if (number < 10)
{
value = "0000" + number.ToString();
}
else if (number < 100)
{
value = "000" + number.ToString();
}
else if (number < 1000)
{
...
}
But this is a bit odd. Is there any built in function for my purpose?

Yes, there is:
string value = String.Format("{0:D5}", number);

According to the MS reference: http://msdn.microsoft.com/en-us/library/dd260048.aspx
You can pad an integer with leading zeros by using the "D" standard
numeric format string together with a precision specifier. You can pad
both integer and floating-point numbers with leading zeros by using a
custom numeric format string.
So:
To display the integer as a decimal value, call its ToString(String)
method, and pass the string "Dn" as the value of the format parameter,
where n represents the minimum length of the string.
Code:
string value = number.ToString("D5");
.NET fiddle: http://dotnetfiddle.net/0U9A6N

You should use the ToString() method with custom formating - see the docs. In particular the 0 specifier.
Replaces the zero with the corresponding digit if one is present; otherwise, zero appears in the result string.
eg,
value = number.Tostring("00000");

string value = number.ToString("00000");

You can do it this way :
number.ToString("00000")

If you wish to return 5 digits numbers, you should use the PadLeft() function;
int Value = 101;
char pad = '0';
String sValue = Value.ToString();
sValue = sValue.s.PadLeft(5, char)
In this case, you don't have to test whether to add 1, 2 or 3 zeros, it'll automatically add the number of zeros needed to make it 5 digits number.

int input_number = Convert.ToInt32(txtinput.Text);
string number_value = input_number.ToString("00000");
I hope that it will solve your problem. It worked well for me in my previous project.
Test this code in your development. It should be worked properly without doubt.

Same as #Jojo's answer, but using C# 6's interpolated strings:
var value = $"{number:00000}";

Apart from String.Format, You can also use String.PadLeft
value = number.ToString().PadLeft(5, '0');

How can I convert string to decimal with trailing zero(s)

Suppose that we have stringvalue=125.32600 when it convert to decimal value with this code
decimal d;
decimal.tryparse(stringvalue,out d)
d value is 125.326
how can I do this convert with final result 125.32600

You cannot because 125.32600 is equal to 125.326. In this case however I guess that you want to print it out with specific format, which can be done like this:
Console.WriteLine(d.ToString("f5"));
Read Standard Numeric Format Strings
UPDATE
Extension method:
public string Format(this decimal source, int precision)
{
if (precision < 0)
{
throw new ArgumentOutOfRangeException("Precision must be a non negative integer");
}
return source.ToString("f" + precision);
}
which can be used like this:
Console.WriteLine(d.Format(5));

Your code works as written (as long as the decimal separator matches your culture):
decimal d;
decimal.TryParse("125.32600", NumberStyles.Number, CultureInfo.InvariantCulture, out d);
s = d.ToString(CultureInfo.InvariantCulture); // 125.32600
Decimal already remembers how many trailing zeros it has. This is caused by decimal representing numbers in non-normalized form, with an integer mantissa and an exponent representing the number of decimal digits. e.g. 125.32600 is represented as 12532600 * 10^-5

The answer is: You can't, at least not like that.
EDIT: correction: decimal already works like that; but you'll still find below a useful way to store your decimals in a DB.
Why? Because that's not how decimals are stored in memory.
Solution: if you need to keep the trailing zeros, just remember the precision explicitly in a separate field (of a class you should create for this purpose); or store the decimals in string form and only convert to decimal as needed.
string strValue = "125.32600";
int precision = strValue.Length - 1; // only the "12332600" part
decimal value = Decimal.Parse(strValue);
stores 8 in precision and 125.326 in value.
To get back the original form:
int afterPt = precision - ((int) value).ToString().Length;
Console.WriteLine(value.ToString("f" + afterPt));
prints
125.32600
P.S. you have to be aware of floating point binary representation issues though, so stuff like 4.05 might be stored as e.g. 4.049999999999999999, so if you need to guarantee this won't happen, use an algorithm that bypasses decimal altogether and uses only integers for storage and computation.
string strValue = "125.32600";
// parse and store
int value = int.Parse(strValue.Replace(".", ""));
int periodIx = strValue.IndexOf(".");
// get back the original representation
string str = value.ToString();
Console.WriteLine(str.Substring(0, periodIx) + "." + str.Substring(periodIx, str.Length - periodIx));
NOTE: Make sure to use , instead of . in locales that need it.

What you can do is count the zeroes in string and then store them in separate DB field. When you want the result with zeroes just concatenate the same no. of zeroes into decimal number string.
ex.
string p="123.456000";
int zeroes=p.Split('0').Length - 1; // guess
decimal value = Decimal.Parse(p); //without zeroes
string valWithZero=value.toString().padRight(zeroes,'0'); //with zeroes

If you really want to have the zeros in the database you could save it as a string, preformatted, but that would be very inefficient.
What is the problem you try to solve by this, there might be a better solution?

Convert string to decimal with format

I need convert a String to a decimal in C#, but this string have different formats.
For example:
"50085"
"500,85"
"500.85"
This should be convert for 500,85 in decimal. Is there is a simplified form to do this convertion using format?

Some cultures use a comma to indicate the floating point. You can test this with the following code on an aspx page:
var x = decimal.Parse("500,85");
Response.Write(x + (decimal)0.15);
This gives the answer 501 when the thread culture has been set to a culture that uses the comma as floating point. You can force this like so:
var x = decimal.Parse("500,85", new NumberFormatInfo() { NumberDecimalSeparator = "," });

While decimal.Parse() is the method you are looking for, you will have to provide a bit more information to it. It will not automatically pick between the 3 formats you give, you will have to tell it which format you are expecting (in the form of an IFormatProvider). Note that even with an IFormatProvider, I don't think "50085" will be properly pulled in.
The only consistent thing I see is that it appears from your examples that you always expect two decimal places of precision. If that is the case, you could strip out all periods and commas and then divide by 100.
Maybe something like:
public decimal? CustomParse(string incomingValue)
{
decimal val;
if (!decimal.TryParse(incomingValue.Replace(",", "").Replace(".", ""), NumberStyles.Number, CultureInfo.InvariantCulture, out val))
return null;
return val / 100;
}

This will work, depending on your culture settings:
string s = "500.85";
decimal d = decimal.Parse(s);
If your culture does not by default allow , instead of . as a decimal point, you will probably need to:
s = s.Replace(',','.');
But will need to check for multiple .'s... this seems to boil down to more of an issue of input sanitization. If you are able to validate and sanitize the input to all conform to a set of rules, the conversion to decimal will be a lot easier.

Try this code below:
string numValue = "500,85";
System.Globalization.CultureInfo culInfo = new System.Globalization.CultureInfo("fr-FR");
decimal decValue;
bool decValid = decimal.TryParse(numValue, System.Globalization.NumberStyles.Number, culInfo.NumberFormat, out decValue);
if (decValid)
{
lblDecNum.Text = Convert.ToString(decValue, culInfo.NumberFormat);
}
Since I am giving a value of 500,85 I will assume that the culture is French and hence the decimal separator is ",". Then decimal.TryParse(numValue, System.Globalization.NumberStyles.Number, culInfo.NumberFormat,out decValue);
will return the value as 500.85 in decValue. Similarly if the user is English US then change the culInfo constructor.

There are numerous ways:
System.Convert.ToDecimal("232.23")
Double.Parse("232.23")
double test;
Double.TryParse("232.23", out test)
Make sure you try and catch...

This is a new feature called Digit Grouping Symbol.
Steps:
Open Region and Language in control panel
Click on Additional setting
On Numbers tab
Set Digit Grouping Symbol as custom setting.
Change comma; replace with (any character as A to Z or {/,}).
Digit Grouping Symbol=e;
Example:
string checkFormate = "123e123";
decimal outPut = 0.0M;
decimal.TryParse(checkFormate, out outPut);
Ans: outPut=123123;

Try This
public decimal AutoParse(string value)
{
if (Convert.ToDecimal("3.3") == ((decimal)3.3))
{
return Convert.ToDecimal(value.Replace(",", "."));
}
else
{
return Convert.ToDecimal(value.Replace(".", ","));
}
}