共用方式為


Byte.Parse Method (String, IFormatProvider)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Converts the string representation of a number in a specified culture-specific format to its Byte equivalent.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Shared Function Parse ( _
    s As String, _
    provider As IFormatProvider _
) As Byte
public static byte Parse(
    string s,
    IFormatProvider provider
)

Parameters

  • provider
    Type: System.IFormatProvider
    An object that supplies culture-specific parsing information about s. If provider is nulla null reference (Nothing in Visual Basic), the current thread culture is used.

Return Value

Type: System.Byte
The Byte value equivalent to the number contained in s.

Exceptions

Exception Condition
ArgumentNullException

s is nulla null reference (Nothing in Visual Basic).

FormatException

s is not of the correct format.

OverflowException

s represents a number less than MinValue or greater than MaxValue.

Remarks

The s parameter contains a number of the form:

[ws][sign]digits[ws]

Elements in square brackets ([ and ]) are optional. The following table describes each element.

Element

Description

ws

Optional white space.

sign

An optional positive sign.

digits

A sequence of digits ranging from 0 to 9.

The s parameter is interpreted using the NumberStyles.Integer style. In addition to the byte value's decimal digits, only leading and trailing spaces together with a leading sign are allowed. (If the sign is present, it must be a positive sign or the method throws an OverflowException.) To explicitly define the style elements together with the culture-specific formatting information that can be present in s, use the Byte.Parse(String, NumberStyles, IFormatProvider) method.

The s parameter is parsed using the formatting information in a NumberFormatInfo object supplied by provider. 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 nulla null reference (Nothing in Visual Basic), the thread current culture is used.

Examples

The following example parses string representations of Byte values with the Parse(String, IFormatProvider) method.

Dim stringToConvert As String 
Dim byteValue As Byte

stringToConvert = " 214 "
Try
   byteValue = Byte.Parse(stringToConvert, CultureInfo.InvariantCulture)
   outputBlock.Text += String.Format("Converted '{0}' to {1}.", stringToConvert, byteValue) + vbCrLf
Catch e As FormatException
   outputBlock.Text += String.Format("Unable to parse '{0}'.", stringToConvert) + vbCrLf
Catch e As OverflowException
   outputBlock.Text += String.Format("'{0}' is greater than {1} or less than {2}.", _
                     stringToConvert, Byte.MaxValue, Byte.MinValue) + vbCrLf
End Try  

stringToConvert = " + 214 "
Try
   byteValue = Byte.Parse(stringToConvert, CultureInfo.InvariantCulture)
   outputBlock.Text += String.Format("Converted '{0}' to {1}.", stringToConvert, byteValue) + vbCrLf
Catch e As FormatException
   outputBlock.Text += String.Format("Unable to parse '{0}'.", stringToConvert) + vbCrLf
Catch e As OverflowException
   outputBlock.Text += String.Format("'{0}' is greater than {1} or less than {2}.", _
                     stringToConvert, Byte.MaxValue, Byte.MinValue) + vbCrLf
End Try  

stringToConvert = " +214 "
Try
   byteValue = Byte.Parse(stringToConvert, CultureInfo.InvariantCulture)
   outputBlock.Text += String.Format("Converted '{0}' to {1}.", stringToConvert, byteValue) + vbCrLf
Catch e As FormatException
   outputBlock.Text += String.Format("Unable to parse '{0}'.", stringToConvert) + vbCrLf
Catch e As OverflowException
   outputBlock.Text += String.Format("'{0}' is greater than {1} or less than {2}.", _
                     stringToConvert, Byte.MaxValue, Byte.MinValue) + vbCrLf
End Try
' The example displays the following output:
'       Converted ' 214 ' to 214.
'       Unable to parse ' + 214 '.
'       Converted ' +214 ' to 214.
string stringToConvert; 
byte byteValue;

stringToConvert = " 214 ";
try {
   byteValue = Byte.Parse(stringToConvert, CultureInfo.InvariantCulture);
   outputBlock.Text += String.Format("Converted '{0}' to {1}.\n", stringToConvert, byteValue);
}
catch (FormatException) {
   outputBlock.Text += String.Format("Unable to parse '{0}'.\n", stringToConvert); }
catch (OverflowException) {
   outputBlock.Text += String.Format("'{0}' is greater than {1} or less than {2}.\n", 
                     stringToConvert, Byte.MaxValue, Byte.MinValue); }

stringToConvert = " + 214 ";
try {
   byteValue = Byte.Parse(stringToConvert, CultureInfo.InvariantCulture);
   outputBlock.Text += String.Format("Converted '{0}' to {1}.\n", stringToConvert, byteValue);
}
catch (FormatException) {
   outputBlock.Text += String.Format("Unable to parse '{0}'.\n", stringToConvert); }
catch (OverflowException) {
   outputBlock.Text += String.Format("'{0}' is greater than {1} or less than {2}.\n", 
                     stringToConvert, Byte.MaxValue, Byte.MinValue); }

stringToConvert = " +214 ";
try {
   byteValue = Byte.Parse(stringToConvert, CultureInfo.InvariantCulture);
   outputBlock.Text += String.Format("Converted '{0}' to {1}.\n", stringToConvert, byteValue);
}
catch (FormatException) {
   outputBlock.Text += String.Format("Unable to parse '{0}'.\n", stringToConvert); }
catch (OverflowException) {
   outputBlock.Text += String.Format("'{0}' is greater than {1} or less than {2}.\n", 
                     stringToConvert, Byte.MaxValue, Byte.MinValue); }
// The example displays the following output:
//       Converted ' 214 ' to 214.
//       Unable to parse ' + 214 '.
//       Converted ' +214 ' to 214.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.