Int32.Parse Method (String, NumberStyles, IFormatProvider)
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Converts the string representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Shared Function Parse ( _
s As String, _
style As NumberStyles, _
provider As IFormatProvider _
) As Integer
public static int Parse(
string s,
NumberStyles style,
IFormatProvider provider
)
Parameters
- s
Type: System.String
A string containing a number to convert.
- style
Type: System.Globalization.NumberStyles
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
Type: System.IFormatProvider
An IFormatProvider that supplies culture-specific information about the format of s.
Return Value
Type: System.Int32
A 32-bit signed integer equivalent to the number specified in s.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentNullException | s is nulla null reference (Nothing in Visual Basic). |
| ArgumentException | style is not a NumberStyles value. -or- style is not a combination of AllowHexSpecifier and HexNumber values. |
| FormatException | s is not in a format compliant with style. |
| OverflowException | s represents a number less than MinValue or greater than MaxValue. -or- s includes non-zero fractional digits. |
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,]digits[.fractional_digist][e[sign]exponential_digits][ws]
Or, if style includes AllowHexSpecifier:
[ws]hexdigits[ws]
Items 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, and it can appear 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 sign. 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. Parentheses can be used in s to indicate a negative value if style includes the NumberStyles.AllowParentheses flag. |
digits fractional_digits exponential_digits |
A sequence of digits from 0 through 9. For fractional_digits, only the digit 0 is valid. |
, |
A culture-specific thousands separator symbol. The thousands separator of the culture specified by provider can appear in s if style includes the NumberStyles.AllowThousands flag. |
. |
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. Only the digit 0 can appear as a fractional digit for the parse operation to succeed; if fractional_digits includes any other digit, an OverflowException is thrown. |
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. |
A string with decimal digits only (which corresponds to the NumberStyles.None style) always parses successfully if it is in the range of the Int32 type. 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 |
|---|---|
Decimal digits only. |
|
The decimal point ( . ) and fractional-digits elements. However, fractional-digits must consist of only one or more 0 digits or an OverflowException is thrown. |
|
The s parameter can also use exponential notation. If s represents a number in exponential notation, it must represent an integer within the range of the Int32 data type without a non-zero fractional component. |
|
The ws element at the beginning of s. |
|
The ws element at the end of s. |
|
A positive sign can appear before digits. |
|
A positive sign can appear after digits. |
|
The sign element in the form of parentheses enclosing the numeric value. |
|
The thousands separator ( , ) element. |
|
The $ element. |
If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value. 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 nulla null reference (Nothing in Visual Basic), the NumberFormatInfo object for the current culture is used.
Examples
The following example uses a variety of style and provider parameters to parse the string representations of Int32 values. It also illustrates some of the different ways the same string can be interpreted depending on the culture whose formatting information is used for the parsing operation.
Imports System.Globalization
Module Example
Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
Convert(outputBlock, "12,000", NumberStyles.Float Or NumberStyles.AllowThousands, _
New CultureInfo("en-GB"))
Convert(outputBlock, "12,000", NumberStyles.Float Or NumberStyles.AllowThousands, _
New CultureInfo("fr-FR"))
Convert(outputBlock, "12,000", NumberStyles.Float, New CultureInfo("en-US"))
Convert(outputBlock, "12 425,00", NumberStyles.Float Or NumberStyles.AllowThousands, _
New CultureInfo("sv-SE"))
Convert(outputBlock, "12,425.00", NumberStyles.Float Or NumberStyles.AllowThousands, _
NumberFormatInfo.InvariantInfo)
Convert(outputBlock, "631,900", NumberStyles.Integer Or NumberStyles.AllowDecimalPoint, _
New CultureInfo("fr-FR"))
Convert(outputBlock, "631,900", NumberStyles.Integer Or NumberStyles.AllowDecimalPoint, _
New CultureInfo("en-US"))
Convert(outputBlock, "631,900", NumberStyles.Integer Or NumberStyles.AllowThousands, _
New CultureInfo("en-US"))
End Sub
Private Sub Convert(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal value As String, ByVal style As NumberStyles, _
ByVal provider As IFormatProvider)
Try
Dim number As Integer = Int32.Parse(value, style, provider)
outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) & vbCrLf
Catch e As FormatException
outputBlock.Text += String.Format("Unable to convert '{0}'.", value) & vbCrLf
Catch e As OverflowException
outputBlock.Text += String.Format("'{0}' is out of range of the Int32 type.", value) & vbCrLf
End Try
End Sub
End Module
' This example displays the following output:
' Converted '12,000' to 12000.
' Converted '12,000' to 12.
' Unable to convert '12,000'.
' Converted '12 425,00' to 12425.
' Converted '12,425.00' to 12425.
' '631,900' is out of range of the Int32 type.
' Unable to convert '631,900'.
' Converted '631,900' to 631900.
using System;
using System.Globalization;
public class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
Convert(outputBlock, "12,000", NumberStyles.Float | NumberStyles.AllowThousands,
new CultureInfo("en-GB"));
Convert(outputBlock, "12,000", NumberStyles.Float | NumberStyles.AllowThousands,
new CultureInfo("fr-FR"));
Convert(outputBlock, "12,000", NumberStyles.Float, new CultureInfo("en-US"));
Convert(outputBlock, "12 425,00", NumberStyles.Float | NumberStyles.AllowThousands,
new CultureInfo("sv-SE"));
Convert(outputBlock, "12,425.00", NumberStyles.Float | NumberStyles.AllowThousands,
NumberFormatInfo.InvariantInfo);
Convert(outputBlock, "631,900", NumberStyles.Integer | NumberStyles.AllowDecimalPoint,
new CultureInfo("fr-FR"));
Convert(outputBlock, "631,900", NumberStyles.Integer | NumberStyles.AllowDecimalPoint,
new CultureInfo("en-US"));
Convert(outputBlock, "631,900", NumberStyles.Integer | NumberStyles.AllowThousands,
new CultureInfo("en-US"));
}
private static void Convert(System.Windows.Controls.TextBlock outputBlock, string value, NumberStyles style,
IFormatProvider provider)
{
try
{
int number = Int32.Parse(value, style, provider);
outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, number) + "\n";
}
catch (FormatException)
{
outputBlock.Text += String.Format("Unable to convert '{0}'.", value) + "\n";
}
catch (OverflowException)
{
outputBlock.Text += String.Format("'{0}' is out of range of the Int32 type.", value) + "\n";
}
}
}
// This example displays the following output:
// Converted '12,000' to 12000.
// Converted '12,000' to 12.
// Unable to convert '12,000'.
// Converted '12 425,00' to 12425.
// Converted '12,425.00' to 12425.
// '631,900' is out of range of the Int32 type.
// Unable to convert '631,900'.
// Converted '631,900' to 631900.
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.
See Also