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System.FormatException when parsing String to double

the Code worked fine in Unity. Now I'm using the samecode in a console Project and im getting a System.FormatException exception.
The code is:
private double ConvertToNumber(string number)
{
return double.Parse(number, numberStyle);
}
parameter when calling are:
number = "3.138924e-002"
numberStyle = NumberStyles.AllowExponent | NumberStyles.AllowDecimalPoint | NumberStyles.AllowLeadingSign
Does anyone see the Error, or knows what might caus this?

The exception is thrown because the string you are providing cannot be converted to a number using the format you specified and your own current cultrue. The latter is implict unless you specify it.
If you are reading this value from a database, you should use the invariant culture (i.e. a culture designed to persist numbers and dates in a consistent way in whatever place you need, except user interfaces).
Your code becomes:
return double.Parse(number, numberStyle, System.Globalization.CultureInfo.InvariantCulture);
Instead, if you need a specific culture, you need to pass the correct culture in place of the invariant one.

#Selvin was right about CultureInfo.InvariantCulture adding it as a param fixed the error.
return double.Parse(number, numberStyle, CultureInfo.InvariantCulture);

String.Format an integer to use a thousands separator with decimal value in danish culture

I have a string totalPRice which holds a value like this 1147,5
I want two things.
1)round the value so that there is always two digits after ,
2)Implement thousands separator in this string, So that final out put will be some thing like this 1.147,50
I have tried some thing like this
String.Format("{0:0.00}", totalPRice)
It does my first requirement correctly by producing an output 1147,50.
But I am way behind in my second requirement. Can any one tell me how I can achieve this?
Note: In danish culture . stands for , and , stands for .

You can refer to Standard Numeric Format Strings and use
string.Format("{0:N2}", 1234.56)
You may also specify the culture manually, if danish is not your default culture:
var danishCulture = CultureInfo.CreateSpecificCulture("da-DK");
string.Format(danishCulture, "{0:N2}", 1234.56);
see MSDN Reference for CultureInfo

You should create a culture-specific CultureInfo object and use it when converting the number into a string. Also, you can set the default culture for your whole program.
Then, your code will look like this:
// create Dennmark-specific culture settings
CultureInfo danishCulture = new CultureInfo("da");
// format the number so that correct Danish decimal and group separators are used
decimal totalPrice = 1234.5m;
Console.WriteLine(totalPrice.ToString("#,###.##", danishCulture));
Note that . and , in the formatting string are specified opposit as you want. This is because they identify decimal and group separators, and are replaced with the correct culture specific-ones.

Try this:
String.Format("{0:N2}", totalPRice)
Another possibility is to use the ToString(string format) overload.
totalPRice.ToString("N2");

If this is a currency value (money!), then it's better to use the current format specifier 'C' or 'c':
string.Format("{0:C}", 1234.56)
Normally I don't write the number of decimal digits since it comes from the international configuration.
You may way to use a different colture specifier if you don't want to use the default one.
var colture = CultureInfo.CreateSpecificCulture("§§§§§");
string.Format(culture, "{0:C}", 1234.56);
where §§§§§ is the string that identifies the desired colture.

Try this for Price format. Put it under template field instead of BoundField.
<%#(decimal.Parse(Eval("YourDataField").ToString())).ToString("N2")%>

Converting string to decimal: how to handle the decimal separator in different cultures

I need to write decimal value to ms access database, but i have a problem with conversion values to decimal in different cultures. Have a values from file, which separates by commma. I try:
public decimal CSingleCulture (string str)
{
string sep = System.Globalization.CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator;
string s = str.Replace(",", sep);
return decimal.Parse(s);
}
if NumberDecimalSeparator = "." then work is good, but if NumberDecimalSeparator = "," problems begin... decimal.Parse(s) always return vlaues separates by dot. In this situation, when inserted into a database error occurs.

The recommended way to deal with this is to store the value as a number rather than a string. Both in the database and in your program. When you do that, your current problem simply never arises.
The only time you deal with numbers in string format is when you display them, or accept user input. In those scenarios you can use the user's culture settings to let them see and use their preferred separator.
Should you ever need to convert between string and number for persistence then you must use culture invariant conversion. This appears to be where you are falling down. I suspect that the file you read has no well-defined format. Make sure that when you read and write the file you use CultureInfo.InvariantCulture. If the file does have a well-defined format that differs from the invariant culture, then use an appropriate specific CultureInfo.

Can't actually understand what is it you're trying to accomplish, and I have to agree with the other answer. But one other thing that's good to know is you can use invariant culture like so:
double.Parse("15.0", CultureInfo.InvariantCulture)
This will always expect dot character to delimit your decimal digits regardless of what is set in current thread's culture.

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.

Can't parse text to Decimal

In Form_load I have
txtAlteFonduri.Text = "5,00";
txtFReparatii.Text = "15,00";
txtFRulment.Text = "20,00";
and in another function I want to parse text as decimal
decimal alteFonduri = Decimal.Parse(txtAlteFonduri.Text);
decimal fondRulment = Decimal.Parse(txtFRulment.Text);
decimal fondRepar = Decimal.Parse(txtFReparatii.Text);
but I have an error in the second line
Input string was not in a correct format.

You need to specifically add the number format. For your examples above, the following should work:
decimal alteFonduri = Decimal.Parse(txtAlteFonduri.Text, CultureInfo.GetCulture("de-DE"));
Otherwise, the system's culture information is used.

You are using a different culture to what decimal.Parse() is expecting (it expects the decimal point '.' but you provide a comma. Using the correct culture should correctly parse the strings, although I can run your code without having any errors...
You can use Decimal.Parse(variable, CultureInfo.GetCultureInfo("Culture-Name"));

You have to use this overload of Decimal.Parse and supply a IFormatProvider matching the culture of your input. You should also consider using one of the Decimal.TryParse methods for better error handling.