How to deal with right zeros in a string to decimal conversion? - c#

in my website i need to read data from a XML, and some of these datas are decimal values.
Sometimes the value comes correct: 1 or 72,59and sometimes the value comes like 1.0000 or 72,590000, how is the best way to convert it to the right format:
ps: I need a string value.
Thanks!

What format are you wanting them to go to, specifically? How many decimals, etc?
If you want always 2 decimals, try a standard numeric formatting such as:
decimal value = 123.456;
Console.WriteLine("Your account balance is {0:F}.", value);
See this MSDN example for other common numeric formatting techniques.

You write that you tried
string.Format("{0:F}","1.00000");
The problem with this is that you're passing a string into the function. Numeric formatting only works on numeric data types. Convert the value to a decimal first and then format it.
Try this
public string ReformatDecimalString(string input)
{
const string formatString = //something
var decimalValue = decimal.Parse(input);
return decimalValue.ToString(formatString);
}
When you are formatting a single numeric value, it's slightly more efficient to use x.ToString(formatString) than string.Format(formatString, x). But note that the specific format string will be different in the two cases.
If your input data has decimal points (not commas) and your computer's culture uses decimal commas, you ought to be able to parse the value correctly by using CultureInfo.InvariantCulture:
var decimalValue = decimal.Parse(input, CultureInfo.InvariantCulture);

If I'm reading your answer correctly, you're trying to convert Integer values you pull from an XML file into string values without trailing zeroes ("ps: I need a string value.")
this code:
decimal test = 20.000000m
test.ToString("G29");
might do what you want

Related

how to convert string to decimal number while maintaining the decimal places in C# [duplicate]

This question already has answers here:
Convert string value into decimal with proper decimal points
(6 answers)
Closed 8 years ago.
In C#, I have a custom string "12.10", when I convert it to decimal it is converted as 12.1 but I need it to be 12.10 in decimal also, please help
Below is the code
string Value = nudEngineeringYears.Value + "." + nudEngineeringMonths.Value;
selStaff.EngineeringExperience = Convert.ToDecimal(Value);
There is no difference between a decimal with value 12.1 or value 12.10.
If you want to display the decimal with 2 decimal place, specify a format string in ToString:
myDouble.ToString("0.00");
Well, as math stays
12.1 == 12.10 == 12.100 == ...
etc. However, you can change number's representation as a string by formatting:
12.1.ToString("F2"); // <- return 12.10 (note "2" in formatting string)
12.1.ToString("F3"); // <- return 12.100 etc.
There's no decimal 12.10, only 12.1.
What you're talking about when you say 12.10 is a possible representation of that value.
There's no difference between 12.10 and 12.1 when talking about numbers, but there's a difference between the string "12.10" and the string "12.1".
So don't confuse a number with its representation (which typically only matters in the front end).
If you want to format your value, you create a string representation of it. See Standard Numeric Format Strings.
You seem to confuse the internal/binary representation of a floating point number with its representation when converted to a string.
Internally a float has always about seven places of precission,
a double about 15 places of precission, a decimal even more.
Only when you format such a binary value to a string you may specify the number of places shown. For formatting use .ToString(format) with the format you need. in your case "F2"

Invariant decimal variable

Please observe following simple code. Why the variable inVarient prints without decimal point. I want decimal point, how to achieve it?
decimal actualVal = 1247315.93m;
string inSwedish = actualVal.ToString(CultureInfo.CreateSpecificCulture("sv-SE"));
decimal inVarient = decimal.Parse(inSwedish, CultureInfo.InvariantCulture);
Console.WriteLine(inSwedish); //prints 1247315,93 (as intended)
Console.WriteLine(inVarient); //prints 124731593 (I need 1247315.93)
Console.Read();
This is because you're trying to parse a string that represents a decimal formatted with the Swedish culture but you're trying to parse it with the invariant culture, which won't treat a comma as a decimal point. You need something like this:
decimal actualVal = 1247315.93m;
var culture = CultureInfo.CreateSpecificCulture("sv-SE");
string inSwedish = actualVal.ToString(culture));
decimal invariant = decimal.Parse(inSwedish, culture);
Console.WriteLine(inSwedish);
Console.WriteLine(invariant.ToString(CultureInfo.InvariantCulture));
Console.Read();
Swedish culture uses , as a decimal separator, the invariant culture uses ., so when it parses a string using the comma as a separator it just ignores it.
The reason why your decimal point disappears here is because in the invariant culture, a comma is a thousands separator, not a decimal separator. Thus, it assumes it can safely ignore commas when parsing a numeric text.
If you go back and forth from a culture to another, this kind of thing is to be expected.
I don't know what your real context is but if you want to recover the numeric as it originally was before it was made a string, you must either use consistent formatters throughout your code or not storing decimals into string variables only to parse them back to decimal again.
If there's no need to serialize anything the latter is the way to go.

How to format string with floating point?

In database I have a PRICE field type of float with value 54342.76 and I want to display it on gridview as 54,342.76. How can format this values?
Try
float f = 54342.76F;
string s = f.ToString("0,0.000", CultureInfo.InvariantCulture);
Console.WriteLine(s);
You could use c specifier instead, however it prints currency sign also.
Use CultureInfo.InvariantCulture as in some localizations , thousands separator may be missing.
Also read Decimal.ToString Method, Standard Numeric Format Strings, Custom Numeric Format Strings
this is what I use:
x.ToString("c")
String.Format("{0:n}", 54342.76F)
The N method is a good solution since it should respect the user's locale while others like:
String.Format("{0:#,###,###.##}", 54342.76F)
Could bypass current culture in some situations. Use {0:n0} instead of {0:n} if you want to display the number without decimals.
In the past I have used this: http://www.codeproject.com/Articles/11531/Money-DataType
It formats money perfectly when used in a DataGridView column.

How do I make sure a decimal is always displayed as xxxx.xxxx positive and negative?

I have a decimal on an object in C#. I want to be able to display it as xxxx.xxxx at the moment the value is -1.61769, basically I want to round the last two digits up and make sure that it only ever has 4 decimal places after the decimal place. Im not sure if this is a Math operation (i.e. Math.Round) or is a validation operation (i.e. string.Format) or both?..
Hope someone can help...
Try this:
string result = d.ToString("0.0000");
You may also want to specify a culture:
CultureInfo cultureInfo = CultureInfo.InvariantCulture;
string result = d.ToString("0.0000", cultureInfo);
Result:
-1.6177
See it working online: ideone
That depends on whether you want at most four decimal places, or exacty four decimal places.
If you round the value, you get at most four decimal places:
value = Math.Round(value, 4);
The value 1.61799 for example would be rounded to 1.6180 and display as 1.618.
If you format the value, you get exactly four decimal places:
string formatted = value.ToString("0.0000");
you have to check with string.Format if you are looking to have a string.
check that link c# double format
if you are looking for keeping the value of the number you should use Math.round
Did you try Math.Abs()?
According to this MSDN-Page it is not possible.
Because it would display a diffierent Value.
Math.Abs(-1.61769).ToString("####.####");

Convert float to string with comma and dot

I have a nullable float. The internal decimal places can be separated with dot or comma e.g. 1.2 or 1,2. I need this float as a string to compare it to a Regex. If I use the Convert.toString method, the float with the comma is 12 and not 1.2. How can I convert a float to String without loosing the comma or the dot? I alredy tried to convert it with diffrent cultures.
Thanks for your help
A solution for this can be the following:
float? num = 1.2f;
string floatAsString = string.Format("{0:f}", num.Value);
Maybe you need to check if the HasValue property is true before you use the value. For more examples: http://alexonasp.net/samples/stringformatting/
String.Format() function with mask. But can you convert your strings to numbers rather than your numbers to strings, for purposes of the comparison? Does it have to be a regex comparison?
Try:
string s = yourFloat.ToString();
Using the invariant culture is recommended if you want to be sure that your output will be in the correct form, but I'd be surprised if there were a culture which doesn't output a comma or a dot.
I would also suggest not using regular expressions to validate the value of a float.
Are you certain that the textbox allows both "." and "," as a decimal-separator (as opposed to a grouping character, also known as a thousands-separator)?
When you are certain that you only get decimal separators and no grouping characters, replace any "," with a "." before using TryParse with an InvariantCulture to convert the string to a float.
OR use the same culture in the code as on the client side, so both will use the same decimal separators.
As others mentioned, a float doesn't have the concept of various decimal separators.
Ok I solved the problem. I did in my xaml a converter which only allows to enter values with commas as separator, so I dont need any checks if there are only two internal decimal places. Thanks for your help
If it's a WinForm Application, there's a static variable Application.CurrentCulture.NumberFormat.NumberDecimalSeparator.
Depending on it's value you get different results when converting ToString().
Try manipulating this parameter to achieve necessary result.

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