Converts the string representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.
Assembly: mscorlib (in mscorlib.dll)
Public Shared Function TryParse ( _
s As [%$TOPIC/zf50za27_en-us_VS_110_1_0_0_0_0%], _
style As [%$TOPIC/zf50za27_en-us_VS_110_1_0_0_0_1%], _
provider As [%$TOPIC/zf50za27_en-us_VS_110_1_0_0_0_2%], _
<[%$TOPIC/zf50za27_en-us_VS_110_1_0_0_0_3%]> ByRef result As [%$TOPIC/zf50za27_en-us_VS_110_1_0_0_0_4%] _
) As [%$TOPIC/zf50za27_en-us_VS_110_1_0_0_0_5%]public static [%$TOPIC/zf50za27_en-us_VS_110_1_0_1_0_0%] TryParse(
[%$TOPIC/zf50za27_en-us_VS_110_1_0_1_0_1%] s,
[%$TOPIC/zf50za27_en-us_VS_110_1_0_1_0_2%] style,
[%$TOPIC/zf50za27_en-us_VS_110_1_0_1_0_3%] provider,
out [%$TOPIC/zf50za27_en-us_VS_110_1_0_1_0_4%] result
)public:
static [%$TOPIC/zf50za27_en-us_VS_110_1_0_2_0_0%] TryParse(
[%$TOPIC/zf50za27_en-us_VS_110_1_0_2_0_1%]^ s,
[%$TOPIC/zf50za27_en-us_VS_110_1_0_2_0_2%] style,
[%$TOPIC/zf50za27_en-us_VS_110_1_0_2_0_3%]^ provider,
[[%$TOPIC/zf50za27_en-us_VS_110_1_0_2_0_4%]] [%$TOPIC/zf50za27_en-us_VS_110_1_0_2_0_5%]% result
)static member TryParse :
s:[%$TOPIC/zf50za27_en-us_VS_110_1_0_3_0_0%] *
style:[%$TOPIC/zf50za27_en-us_VS_110_1_0_3_0_1%] *
provider:[%$TOPIC/zf50za27_en-us_VS_110_1_0_3_0_2%] *
result:[%$TOPIC/zf50za27_en-us_VS_110_1_0_3_0_3%] byref -> [%$TOPIC/zf50za27_en-us_VS_110_1_0_3_0_4%]Parameters
- s
- Type:
SystemString
A string containing a number to convert. The string is interpreted using the style specified by style.
- style
- Type:
System.GlobalizationNumberStyles
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:
SystemIFormatProvider
An object that supplies culture-specific formatting information about s.
- result
- Type:
SystemInt32
When this method returns, contains the 32-bit signed integer value equivalent to the number contained in s, if the conversion succeeded, or zero if the conversion failed. The conversion fails if the s parameter is , is not in a format compliant with style, or represents a number less than MinValue or greater than MaxValue. This parameter is passed uninitialized.
| Exception | Condition |
|---|---|
| ArgumentException | style is not a NumberStyles value. -or- style is not a combination of AllowHexSpecifier and HexNumber values. |
The TryParse method is like the Parse method, except the TryParse method does not throw an exception if the conversion fails. It eliminates the need to use exception handling to test for a FormatException in the event that s is invalid and cannot be parsed successfully.
The style parameter defines the style elements (such as white space or a positive or negative 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_digits][e[sign]digits][ws]
Or, if the style parameter 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 NumberStylesAllowLeadingWhite flag, or at the end of s if style includes the NumberStylesAllowTrailingWhite flag. |
$ | A culture-specific currency symbol. Its position in the string is defined by the 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 NumberStylesAllowCurrencySymbol flag. |
sign | An optional sign. A sign symbol can appear in s if style includes the NumberStylesAllowLeadingSign or NumberStylesAllowTrailingSign flags. |
digits | A sequence of digits from 0 through 9. |
, | A culture-specific thousands separator. The thousands separator of the culture specified by provider can appear in s if style includes the NumberStylesAllowThousands 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 NumberStylesAllowDecimalPoint flag. |
fractional_digits | One or more occurrences of the digit 0. Fractional digits can appear in s only if style includes the NumberStylesAllowDecimalPoint 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 NumberStylesAllowExponent 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 NumberStylesNone flag) 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 |
|---|---|
Decimal digits only. | |
The decimal point (.) and fractional_digits elements. However, fractional_digits must consist of only one or more 0 digits or the method returns false. | |
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 sign can appear before digits. | |
A sign can appear after digits. | |
The sign element in the form of parentheses enclosing the numeric value. | |
The thousands separator (,) element. | |
The $ element. | |
All elements. The s parameter cannot represent a hexadecimal number or a number in exponential notation. | |
The ws element at the beginning or end of s, sign at the beginning of s, and the decimal point (.) symbol. The s parameter can also use exponential notation. | |
The ws, sign, thousands separator (,), and decimal point (.) elements. | |
All styles, except s cannot represent a hexadecimal number. |
If the NumberStylesAllowHexSpecifier flag is used, s must be a hexadecimal value. The only other flags that can be present in style are NumberStylesAllowLeadingWhite and NumberStylesAllowTrailingWhite. (The NumberStyles enumeration has a composite style, NumberStylesHexNumber, that includes both white space flags.)
The provider parameter is an IFormatProvider implementation, such as a CultureInfo object or a NumberFormatInfo object, whose GetFormat method returns a NumberFormatInfo object. The NumberFormatInfo object provides culture-specific information about the format of s. If provider is , the NumberFormatInfo object for the current culture is used.
The following example calls the Int32TryParse(String, NumberStyles, IFormatProvider, Int32) method with a number of different string and NumberStyles values.
Imports System.Globalization
Module StringParsing
Public Sub Main()
Dim numericString As String
Dim styles As NumberStyles
numericString = "106779"
styles = NumberStyles.Integer
CallTryParse(numericString, styles)
numericString = "-30677"
styles = NumberStyles.None
CallTryParse(numericString, styles)
styles = NumberStyles.AllowLeadingSign
CallTryParse(numericString, styles)
numericString = "301677-"
CallTryParse(numericString, styles)
styles = styles Or NumberStyles.AllowTrailingSign
CallTryParse(numericString, styles)
numericString = "$10634"
styles = NumberStyles.Integer
CallTryParse(numericString, styles)
styles = NumberStyles.Integer Or NumberStyles.AllowCurrencySymbol
CallTryParse(numericString, styles)
numericString = "10345.00"
styles = NumberStyles.Integer Or NumberStyles.AllowDecimalPoint
CallTryParse(numericString, styles)
numericString = "10345.72"
styles = NumberStyles.Integer Or NumberStyles.AllowDecimalPoint
CallTryParse(numericString, styles)
numericString = "22,593"
styles = NumberStyles.Integer Or NumberStyles.AllowThousands
CallTryParse(numericString, styles)
numericString = "12E-01"
styles = NumberStyles.Integer Or NumberStyles.AllowExponent
CallTryParse(numericString, styles)
numericString = "12E03"
CallTryParse(numericString, styles)
numericString = "80c1"
CallTryParse(numericString, NumberStyles.HexNumber)
numericString = "0x80C1"
CallTryParse(numericString, NumberStyles.HexNumber)
End Sub
Private Sub CallTryParse(stringToConvert As String, styles AS NumberStyles)
Dim number As Integer
Dim provider As CultureInfo
' If currency symbol is allowed, use en-US culture.
If CBool(styles And NumberStyles.AllowCurrencySymbol) Then
provider = CultureInfo.CurrentCulture
Else
provider = New CultureInfo("en-US")
End If
Dim result As Boolean = Int32.TryParse(stringToConvert, styles, _
provider, number)
If result Then
Console.WriteLine("Converted '{0}' to {1}.", stringToConvert, number)
Else
Console.WriteLine("Attempted conversion of '{0}' failed.", _
Convert.ToString(stringToConvert))
End If
End Sub
End Module
' The example displays the following output to the console:
' Converted '106779' to 106779.
' Attempted conversion of '-30677' failed.
' Converted '-30677' to -30677.
' Attempted conversion of '301677-' failed.
' Converted '301677-' to -301677.
' Attempted conversion of '$10634' failed.
' Converted '$10634' to 10634.
' Converted '10345.00' to 10345.
' Attempted conversion of '10345.72' failed.
' Converted '22,593' to 22593.
' Attempted conversion of '12E-01' failed.
' Converted '12E03' to 12000.
' Converted '80c1' to 32961.
' Attempted conversion of '0x80C1' failed.using System;
using System.Globalization;
public class StringParsing
{
public static void Main()
{
string numericString;
NumberStyles styles;
numericString = "106779";
styles = NumberStyles.Integer;
CallTryParse(numericString, styles);
numericString = "-30677";
styles = NumberStyles.None;
CallTryParse(numericString, styles);
styles = NumberStyles.AllowLeadingSign;
CallTryParse(numericString, styles);
numericString = "301677-";
CallTryParse(numericString, styles);
styles = styles | NumberStyles.AllowTrailingSign;
CallTryParse(numericString, styles);
numericString = "$10634";
styles = NumberStyles.Integer;
CallTryParse(numericString, styles);
styles = NumberStyles.Integer | NumberStyles.AllowCurrencySymbol;
CallTryParse(numericString, styles);
numericString = "10345.00";
styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
CallTryParse(numericString, styles);
numericString = "10345.72";
styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
CallTryParse(numericString, styles);
numericString = "22,593";
styles = NumberStyles.Integer | NumberStyles.AllowThousands;
CallTryParse(numericString, styles);
numericString = "12E-01";
styles = NumberStyles.Integer | NumberStyles.AllowExponent;
CallTryParse(numericString, styles);
numericString = "12E03";
CallTryParse(numericString, styles);
numericString = "80c1";
CallTryParse(numericString, NumberStyles.HexNumber);
numericString = "0x80C1";
CallTryParse(numericString, NumberStyles.HexNumber);
}
private static void CallTryParse(string stringToConvert, NumberStyles styles)
{
int number;
CultureInfo provider;
// If currency symbol is allowed, use en-US culture.
if ((styles & NumberStyles.AllowCurrencySymbol) > 0)
provider = new CultureInfo("en-US");
else
provider = CultureInfo.InvariantCulture;
bool result = Int32.TryParse(stringToConvert, styles,
provider, out number);
if (result)
Console.WriteLine("Converted '{0}' to {1}.", stringToConvert, number);
else
Console.WriteLine("Attempted conversion of '{0}' failed.",
Convert.ToString(stringToConvert));
}
}
// The example displays the following output to the console:
// Converted '106779' to 106779.
// Attempted conversion of '-30677' failed.
// Converted '-30677' to -30677.
// Attempted conversion of '301677-' failed.
// Converted '301677-' to -301677.
// Attempted conversion of '$10634' failed.
// Converted '$10634' to 10634.
// Converted '10345.00' to 10345.
// Attempted conversion of '10345.72' failed.
// Converted '22,593' to 22593.
// Attempted conversion of '12E-01' failed.
// Converted '12E03' to 12000.
// Converted '80c1' to 32961.
// Attempted conversion of '0x80C1' failed.using namespace System;
using namespace System::Globalization;
void CallTryParse(String^ stringToConvert, NumberStyles styles)
{
Int32 number;
CultureInfo^ provider;
// If currency symbol is allowed, use en-US culture.
if (((Int32) (styles & NumberStyles::AllowCurrencySymbol)) > 0)
provider = gcnew CultureInfo("en-US");
else
provider = CultureInfo::InvariantCulture;
bool result = Int32::TryParse(stringToConvert, styles,
provider, number);
if (result)
Console::WriteLine("Converted '{0}' to {1}.", stringToConvert, number);
else
Console::WriteLine("Attempted conversion of '{0}' failed.",
Convert::ToString(stringToConvert));
}
void main()
{
String^ numericString;
NumberStyles styles;
numericString = "106779";
styles = NumberStyles::Integer;
CallTryParse(numericString, styles);
numericString = "-30677";
styles = NumberStyles::None;
CallTryParse(numericString, styles);
styles = NumberStyles::AllowLeadingSign;
CallTryParse(numericString, styles);
numericString = "301677-";
CallTryParse(numericString, styles);
styles = styles | NumberStyles::AllowTrailingSign;
CallTryParse(numericString, styles);
numericString = "$10634";
styles = NumberStyles::Integer;
CallTryParse(numericString, styles);
styles = NumberStyles::Integer | NumberStyles::AllowCurrencySymbol;
CallTryParse(numericString, styles);
numericString = "10345.00";
styles = NumberStyles::Integer | NumberStyles::AllowDecimalPoint;
CallTryParse(numericString, styles);
numericString = "10345.72";
styles = NumberStyles::Integer | NumberStyles::AllowDecimalPoint;
CallTryParse(numericString, styles);
numericString = "22,593";
styles = NumberStyles::Integer | NumberStyles::AllowThousands;
CallTryParse(numericString, styles);
numericString = "12E-01";
styles = NumberStyles::Integer | NumberStyles::AllowExponent;
CallTryParse(numericString, styles);
numericString = "12E03";
CallTryParse(numericString, styles);
numericString = "80c1";
CallTryParse(numericString, NumberStyles::HexNumber);
numericString = "0x80C1";
CallTryParse(numericString, NumberStyles::HexNumber);
Console::ReadLine();
}
// The example displays the following output:
// Converted '106779' to 106779.
// Attempted conversion of '-30677' failed.
// Converted '-30677' to -30677.
// Attempted conversion of '301677-' failed.
// Converted '301677-' to -301677.
// Attempted conversion of '$10634' failed.
// Converted '$10634' to 10634.
// Converted '10345.00' to 10345.
// Attempted conversion of '10345.72' failed.
// Converted '22,593' to 22593.
// Attempted conversion of '12E-01' failed.
// Converted '12E03' to 12000.
// Converted '80c1' to 32961.
// Attempted conversion of '0x80C1' failed.Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
