Byte.Parse Method (System) (original) (raw)
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Converts the string representation of a number in a specified style and culture-specific format to its Byte equivalent.
public:
static System::Byte Parse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider);
public:
static System::Byte Parse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider) = System::Numerics::INumberBase<System::Byte>::Parse;
public static byte Parse(string s, System.Globalization.NumberStyles style, IFormatProvider provider);
public static byte Parse(string s, System.Globalization.NumberStyles style, IFormatProvider? provider);
static member Parse : string * System.Globalization.NumberStyles * IFormatProvider -> byte
Public Shared Function Parse (s As String, style As NumberStyles, provider As IFormatProvider) As Byte
Parameters
s
A string that contains a number to convert. The string is interpreted using the style specified by style
.
style
A bitwise combination of enumeration values that indicates the style elements that can be present in s
. A typical value to specify is Integer.
provider
An object that supplies culture-specific information about the format of s
. If provider
is null
, the thread current culture is used.
Returns
A byte value that is equivalent to the number contained in s
.
Implements
Exceptions
s
is not of the correct format.
Examples
The following code example parses string representations of Byte
values with this overload of the Byte.Parse(String, NumberStyles, IFormatProvider) method.
NumberStyles style;
CultureInfo culture;
string value;
byte number;
// Parse number with decimals.
// NumberStyles.Float includes NumberStyles.AllowDecimalPoint.
style = NumberStyles.Float;
culture = CultureInfo.CreateSpecificCulture("fr-FR");
value = "12,000";
number = Byte.Parse(value, style, culture);
Console.WriteLine("Converted '{0}' to {1}.", value, number);
culture = CultureInfo.CreateSpecificCulture("en-GB");
try
{
number = Byte.Parse(value, style, culture);
Console.WriteLine("Converted '{0}' to {1}.", value, number);
}
catch (FormatException) {
Console.WriteLine("Unable to parse '{0}'.", value); }
value = "12.000";
number = Byte.Parse(value, style, culture);
Console.WriteLine("Converted '{0}' to {1}.", value, number);
// The example displays the following output to the console:
// Converted '12,000' to 12.
// Unable to parse '12,000'.
// Converted '12.000' to 12.
// Parse number with decimals.
// NumberStyles.Float includes NumberStyles.AllowDecimalPoint.
let style = NumberStyles.Float
let culture = CultureInfo.CreateSpecificCulture "fr-FR"
let value = "12,000"
let number = Byte.Parse(value, style, culture)
printfn $"Converted '{value}' to {number}."
let culture = CultureInfo.CreateSpecificCulture "en-GB"
try
let number = Byte.Parse(value, style, culture)
printfn $"Converted '{value}' to {number}."
with :? FormatException ->
printfn $"Unable to parse '{value}'."
let value = "12.000"
let number = Byte.Parse(value, style, culture)
printfn $"Converted '{value}' to {number}."
// The example displays the following output to the console:
// Converted '12,000' to 12.
// Unable to parse '12,000'.
// Converted '12.000' to 12.
Dim style As NumberStyles
Dim culture As CultureInfo
Dim value As String
Dim number As Byte
' Parse number with decimals.
' NumberStyles.Float includes NumberStyles.AllowDecimalPoint.
style = NumberStyles.Float
culture = CultureInfo.CreateSpecificCulture("fr-FR")
value = "12,000"
number = Byte.Parse(value, style, culture)
Console.WriteLine("Converted '{0}' to {1}.", value, number)
culture = CultureInfo.CreateSpecificCulture("en-GB")
Try
number = Byte.Parse(value, style, culture)
Console.WriteLine("Converted '{0}' to {1}.", value, number)
Catch e As FormatException
Console.WriteLine("Unable to parse '{0}'.", value)
End Try
value = "12.000"
number = Byte.Parse(value, style, culture)
Console.WriteLine("Converted '{0}' to {1}.", value, number)
' The example displays the following output to the console:
' Converted '12,000' to 12.
' Unable to parse '12,000'.
' Converted '12.000' to 12.
Remarks
The style
parameter defines the style elements (such as white space or the positive sign) that are allowed in the s
parameter for the parse operation to succeed. It must be a combination of bit flags from the NumberStyles enumeration. Depending on the value of style
, the s
parameter may include the following elements:
[ws][$][sign]digits[.fractional_digits][e[sign]digits][ws]
Or, if the style
parameter includes AllowHexSpecifier:
[ws]hexdigits[ws]
Elements in square brackets ([ and ]) are optional. The following table describes each element.
Element | Description |
---|---|
ws | Optional white space. White space can appear at the beginning of s if style includes the NumberStyles.AllowLeadingWhite flag, or at the end of s if style includes the NumberStyles.AllowTrailingWhite flag. |
$ | A culture-specific currency symbol. Its position in the string is defined by the NumberFormatInfo.CurrencyPositivePattern property of the NumberFormatInfo object returned by the GetFormat method of the provider parameter. The currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag. |
sign | An optional positive sign. (The method throws an OverflowException if a negative sign is present in s.) The sign can appear at the beginning of s if style includes the NumberStyles.AllowLeadingSign flag, or at the end of s if style includes the NumberStyles.AllowTrailingSign flag. |
digits | A sequence of digits from 0 through 9. |
. | A culture-specific decimal point symbol. The decimal point symbol of the culture specified by provider can appear in s if style includes the NumberStyles.AllowDecimalPoint flag. |
fractional_digits | One or more occurrences of the digit 0. Fractional digits can appear in s only if style includes the NumberStyles.AllowDecimalPoint flag. |
e | The e or E character, which indicates that the value is represented in exponential notation. The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag. |
hexdigits | A sequence of hexadecimal digits from 0 through f, or 0 through F. |
Note
Any terminating NUL (U+0000) characters in s
are ignored by the parsing operation, regardless of the value of the style
argument.
A string with decimal digits only (which corresponds to the NumberStyles.None style) always parses successfully. Most of the remaining NumberStyles members control elements that may be but are not required to be present in this input string. The following table indicates how individual NumberStyles members affect the elements that may be present in s
.
Non-composite NumberStyles values | Elements permitted in s in addition to digits |
---|---|
NumberStyles.None | Decimal digits only. |
NumberStyles.AllowDecimalPoint | The . and fractional_digits elements. However, fractional_digits must consist of only one or more 0 digits or an OverflowException is thrown. |
NumberStyles.AllowExponent | The s parameter can also use exponential notation. |
NumberStyles.AllowLeadingWhite | The ws element at the beginning of s. |
NumberStyles.AllowTrailingWhite | The ws element at the end of s. |
NumberStyles.AllowLeadingSign | A positive sign can appear before digits. |
NumberStyles.AllowTrailingSign | A positive sign can appear after digits. |
NumberStyles.AllowParentheses | Although this flag is supported, the use of parentheses in s results in an OverflowException. |
NumberStyles.AllowThousands | Although the group separator symbol can appear in s, it can be preceded by only one or more 0 digits. |
NumberStyles.AllowCurrencySymbol | The $ element. |
If the NumberStyles.AllowHexSpecifier flag is used, s
must be a hexadecimal value without a prefix. For example, "F3" parses successfully, but "0xF3" does not. The only other flags that can be present in style
are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. (The NumberStyles enumeration has a composite number style, NumberStyles.HexNumber, that includes both white space flags.)
The provider
parameter is an IFormatProvider implementation, such as a NumberFormatInfo or CultureInfo object. The provider
parameter supplies culture-specific information used in parsing. If provider
is null
, the thread current culture is used.