Converts the string representation of a number in a specified style and culture-specific format to its 64-bit signed integer equivalent. A return value indicates whether the conversion succeeded or failed.
public:
static bool TryParse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] long % result);
public:
static bool TryParse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] long % result) = System::Numerics::INumberBase<long>::TryParse;
public static bool TryParse(string s, System.Globalization.NumberStyles style, IFormatProvider provider, out long result);
public static bool TryParse(string? s, System.Globalization.NumberStyles style, IFormatProvider? provider, out long result);
static member TryParse : string * System.Globalization.NumberStyles * IFormatProvider * int64 -> bool
Public Shared Function TryParse (s As String, style As NumberStyles, provider As IFormatProvider, ByRef result As Long) As Boolean
Parameters
A string containing a number to convert. The string is interpreted using the style specified by 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.
An object that supplies culture-specific formatting information about s
.
When this method returns, contains the 64-bit signed integer value equivalent of the number contained in s
, if the conversion succeeded, or zero if the conversion failed. The conversion fails if the s
parameter is null
or Empty, is not in a format compliant with style
, or represents a number less than Int64.MinValue or greater than Int64.MaxValue. This parameter is passed uninitialized; any value originally supplied in result
will be overwritten.
true
if s
was converted successfully; otherwise, false
.
The following example calls the TryParse(String, NumberStyles, IFormatProvider, Int64) method with a number of different string and NumberStyles values.
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 = "$10634";
styles = NumberStyles.Integer;
CallTryParse(numericString, styles);
styles = NumberStyles.Integer | NumberStyles.AllowCurrencySymbol;
CallTryParse(numericString, styles);
numericString = "10345.00";
styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
CallTryParse(numericString, styles);
numericString = "10345.72";
styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
CallTryParse(numericString, styles);
numericString = "22,593";
styles = NumberStyles.Integer | NumberStyles.AllowThousands;
CallTryParse(numericString, styles);
numericString = "12E-01";
styles = NumberStyles.Integer | NumberStyles.AllowExponent;
CallTryParse(numericString, styles);
numericString = "12E03";
CallTryParse(numericString, styles);
numericString = "80c1";
CallTryParse(numericString, NumberStyles.HexNumber);
numericString = "0x80C1";
CallTryParse(numericString, NumberStyles.HexNumber);
}
private static void CallTryParse(string stringToConvert, NumberStyles styles)
{
CultureInfo provider;
// If currency symbol is allowed, use en-US culture.
if ((styles & NumberStyles.AllowCurrencySymbol) > 0)
provider = new CultureInfo("en-US");
else
provider = CultureInfo.InvariantCulture;
bool success = Int64.TryParse(stringToConvert, styles,
provider, out long number);
if (success)
Console.WriteLine($"Converted '{stringToConvert}' to {number}.");
else
Console.WriteLine($"Attempted conversion of '{stringToConvert}' failed.");
}
}
// 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.
open System
open System.Globalization
let callTryParse (stringToConvert: string) styles =
let provider =
// If currency symbol is allowed, use en-US culture.
if int (styles &&& NumberStyles.AllowCurrencySymbol) > 0 then
CultureInfo "en-US"
else
CultureInfo.InvariantCulture
match Int64.TryParse(stringToConvert, styles, provider) with
| true, number ->
printfn $"Converted '{stringToConvert}' to {number}."
| _ ->
printfn $"Attempted conversion of '{stringToConvert}' failed."
[<EntryPoint>]
let main _ =
let numericString = "106779"
let styles = NumberStyles.Integer
callTryParse numericString styles
let numericString = "-30677"
let styles = NumberStyles.None
callTryParse numericString styles
let styles = NumberStyles.AllowLeadingSign
callTryParse numericString styles
let numericString = "301677-"
callTryParse numericString styles
let styles = styles ||| NumberStyles.AllowTrailingSign
callTryParse numericString styles
let numericString = "$10634"
let styles = NumberStyles.Integer
callTryParse numericString styles
let styles = NumberStyles.Integer ||| NumberStyles.AllowCurrencySymbol
callTryParse numericString styles
let numericString = "10345.00"
let styles = NumberStyles.Integer ||| NumberStyles.AllowDecimalPoint
callTryParse numericString styles
let numericString = "10345.72"
let styles = NumberStyles.Integer ||| NumberStyles.AllowDecimalPoint
callTryParse numericString styles
let numericString = "22,593"
let styles = NumberStyles.Integer ||| NumberStyles.AllowThousands
callTryParse numericString styles
let numericString = "12E-01"
let styles = NumberStyles.Integer ||| NumberStyles.AllowExponent
callTryParse numericString styles
let numericString = "12E03"
callTryParse numericString styles
let numericString = "80c1"
callTryParse numericString NumberStyles.HexNumber
let numericString = "0x80C1"
callTryParse numericString NumberStyles.HexNumber
0
// 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.
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 Long
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 = Int64.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 '$10634' to 10634.
' Converted '10345.00' to 10345.
' Attempted conversion of '10345.72' failed.
' Converted '22,593' to 22593.
' Attempted conversion of '12E-01' failed.
' Converted '12E03' to 12000.
' Converted '80c1' to 32961.
' Attempted conversion of '0x80C1' failed.
Remarks
The TryParse method is like the Parse method, except the TryParse method does not throw an exception if the conversion fails. It eliminates the need to use exception handling to test for a FormatException in the event that s
is invalid and cannot be parsed successfully.
The style
parameter defines the style elements (such as white space or a positive or negative sign) that are allowed in the s
parameter for the parse operation to succeed. It must be a combination of bit flags from the NumberStyles enumeration. Depending on the value of style
,the s
parameter may include the following elements:
[ws][$][sign][digits,]digits[.fractional_digits][e[sign]exponential_digits][ws]
Or, if the style
parameter includes NumberStyles.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 ofs
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 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. A sign symbol can appear in s
if style
includes the NumberStyles.AllowLeadingSign or NumberStyles.AllowTrailingSign flags. 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. The thousands separator of the culture specified byprovider
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. 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 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
.
If the NumberStyles.AllowHexSpecifier flag is used, s
must be a hexadecimal value without a prefix. For example, "C9AF3" parses successfully, but "0xC9AF3" does not. The only other flags that can be present in style
are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. (The NumberStyles enumeration has a composite style, NumberStyles.HexNumber, 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 null
, the NumberFormatInfo object for the current culture is used.
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