Int16.TryParse 方法

将数字的字符串表示形式转换为它的等效 16 位有符号整数。Converts the string representation of a number to its 16-bit signed integer equivalent. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded or failed.

public:
 static bool TryParse(System::String ^ s, [Runtime::InteropServices::Out] short % result);

public static bool TryParse (string s, out short result);

static member TryParse : string * int16 -> bool

Public Shared Function TryParse (s As String, ByRef result As Short) As Boolean

参数

返回

示例

下面的示例使用多个不同的字符串值调用 Int16.TryParse(String, Int16) 方法。The following example calls the Int16.TryParse(String, Int16) method with a number of different string values.

using System;

public class StringParsing
{
   public static void Main()
   {
      TryToParse(null);
      TryToParse("16051");
      TryToParse("9432.0");
      TryToParse("16,667");
      TryToParse("   -322   ");
      TryToParse("+4302");
      TryToParse("(100);");
      TryToParse("01FA");
   }

   private static void TryToParse(string value)
   {
      short number;
      bool result = Int16.TryParse(value, out number);
      if (result)
      {
         Console.WriteLine("Converted '{0}' to {1}.", value, number);         
      }
      else
      {
         if (value == null) value = ""; 
         Console.WriteLine("Attempted conversion of '{0}' failed.", value);
      }
   }
}
// The example displays the following output to the console:
//       Attempted conversion of '' failed.
//       Converted '16051' to 16051.
//       Attempted conversion of '9432.0' failed.
//       Attempted conversion of '16,667' failed.
//       Converted '   -322   ' to -322.
//       Converted '+4302' to 4302.
//       Attempted conversion of '(100)' failed.
//       Attempted conversion of '01FA' failed.

Module StringParsing
   Public Sub Main()
      TryToParse(Nothing)
      TryToParse("16051")
      TryToParse("9432.0")
      TryToParse("16,667")
      TryToParse("   -322   ")
      TryToParse("+4302")
      TryToParse("(100)")
      TryToParse("01FA")
      
   End Sub
   
   Private Sub TryToParse(value As String)
      Dim number As Int16
      Dim result As Boolean = Int16.TryParse(value, number)
      If result Then
         Console.WriteLine("Converted '{0}' to {1}.", value, number)
      Else
         If value Is Nothing Then value = "" 
         Console.WriteLine("Attempted conversion of '{0}' failed.", value)
      End If     
   End Sub
End Module
' The example displays the following output to the console:
'       Attempted conversion of '' failed.
'       Converted '16051' to 16051.
'       Attempted conversion of '9432.0' failed.
'       Attempted conversion of '16,667' failed.
'       Converted '   -322   ' to -322.
'       Converted '+4302' to 4302.
'       Attempted conversion of '(100)' failed.
'       Attempted conversion of '01FA' failed.

在此示例中，TryParse(String, Int16) 方法无法转换的某些字符串是：Some of the strings that the TryParse(String, Int16) method is unable to convert in this example are:

• "9432.0"."9432.0". 转换失败，因为字符串不能包含小数分隔符;它必须仅包含整数位数。The conversion fails because the string cannot contain a decimal separator; it must contain integral digits only.

• "16,667"."16,667". 转换失败，因为字符串不能包含组分隔符;它必须仅包含整数位数。The conversion fails because the string cannot contain group separators; it must contain integral digits only.

• "(100)"."(100)". 转换失败的原因是，字符串不能包含由当前区域性的 NumberFormatInfo.NegativeSign 和 NumberFormatInfo.NumberNegativePattern 属性所定义的负号。The conversion fails because the string cannot contain a negative sign other than the one defined by the current culture's NumberFormatInfo.NegativeSign and NumberFormatInfo.NumberNegativePattern properties.

• "01FA"."01FA". 转换失败，因为字符串不能包含十六进制数字;它只能包含十进制数字。The conversion fails because the string cannot contain hexadecimal digits; it must contain decimal digits only.

注解

Int16.TryParse(String, Int16) 方法与 Int16.Parse(String) 方法的不同之处在于，返回一个布尔值，该值指示分析操作是否成功，而不是返回已分析的 Int16 值。The Int16.TryParse(String, Int16) method differs from the Int16.Parse(String) method by returning a Boolean value that indicates whether the parse operation succeeded instead of returning the parsed Int16 value. 当 s 无效且无法成功分析时，无需使用异常处理来测试 FormatException。It eliminates the need to use exception handling to test for a FormatException in the event that s is invalid and cannot be successfully parsed.

s 参数应是数字的字符串表示形式：The s parameter should be the string representation of a number in the form:

[ws][sign]digits[ws][ws][sign]digits[ws]

方括号（[和]）中的项是可选的。Items in square brackets ([ and ]) are optional. 下表对每个元素进行了描述。The following table describes each element.

元素Element	说明Description
wsws	可选空白。Optional white space.
signsign	一个可选的符号。An optional sign.
digitsdigits	介于0到9之间的一系列数字。A sequence of digits ranging from 0 to 9.

使用 NumberStyles.Integer 样式对 s 参数进行解释。The s parameter is interpreted using the NumberStyles.Integer style. 除十进制数字外，只允许使用前导和尾随空格以及前导符号。In addition to the decimal digits, only leading and trailing spaces together with a leading sign are allowed. 若要将样式元素与 s中可以存在的区域性特定格式设置信息一起显式定义，请使用 Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) 方法。To explicitly define the style elements together with the culture-specific formatting information that can be present in s, use the Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) method.

s 参数是使用为当前系统区域性初始化 NumberFormatInfo 对象中的格式设置信息分析的。The s parameter is parsed using the formatting information in a NumberFormatInfo object that is initialized for the current system culture. 有关详细信息，请参阅 CurrentInfo。For more information, see CurrentInfo.

TryParse 方法的此重载将 s 参数中的所有数字解释为十进制数字。This overload of the TryParse method interprets all digits in the s parameter as decimal digits. 若要分析十六进制数的字符串表示形式，请调用 Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) 重载。To parse the string representation of a hexadecimal number, call the Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) overload.

另请参阅

• Parse(String)
• ToString()
• 分析 .NET 中的数字字符串Parsing Numeric Strings in .NET
• 示例： .NET Core WinForms 格式设置实用工具C#（）Sample: .NET Core WinForms Formatting Utility (C#)
• 示例： .NET Core WinForms 格式设置实用工具（Visual Basic）Sample: .NET Core WinForms Formatting Utility (Visual Basic)

将指定样式和区域性特定格式的数字的范围表示形式转换为它的等效 16 位带符号整数。Converts the span representation of a number in a specified style and culture-specific format to its 16-bit signed integer equivalent. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded or failed.

public:
 static bool TryParse(ReadOnlySpan<char> s, [Runtime::InteropServices::Out] short % result);

public static bool TryParse (ReadOnlySpan<char> s, out short result);

static member TryParse : ReadOnlySpan<char> * int16 -> bool

Public Shared Function TryParse (s As ReadOnlySpan(Of Char), ByRef result As Short) As Boolean

参数

返回

将指定样式和区域性特定格式的数字的字符串表示形式转换为它的等效 16 位有符号整数。Converts the string representation of a number in a specified style and culture-specific format to its 16-bit signed integer equivalent. 一个指示转换是否成功的返回值。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] short % result);

public static bool TryParse (string s, System.Globalization.NumberStyles style, IFormatProvider provider, out short result);

static member TryParse : string * System.Globalization.NumberStyles * IFormatProvider * int16 -> bool

Public Shared Function TryParse (s As String, style As NumberStyles, provider As IFormatProvider, ByRef result As Short) As Boolean

参数

返回

异常

示例

下面的示例使用多个不同的字符串值调用 Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) 方法。The following example calls the Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) method with a number of different string values.

using System;
using System.Globalization;

public class StringParsing
{
   public static void Main()
   {
      string numericString;
      NumberStyles styles;
      
      numericString = "10677";
      styles = NumberStyles.Integer;
      CallTryParse(numericString, styles);

      numericString = "-30677";
      styles = NumberStyles.None;
      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)
   {
      short number;
      bool result = Int16.TryParse(stringToConvert, styles, 
                                   CultureInfo.InvariantCulture, 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 '10677' to 10677.
//       Attempted conversion of '-30677' failed.
//       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 -32575.
//       Attempted conversion of '0x80C1' failed.

Imports System.Globalization

Module StringParsing
   Public Sub Main()
      Dim numericString As String
      Dim styles As NumberStyles
      
      numericString = "10677"
      styles = NumberStyles.Integer
      CallTryParse(numericString, styles)
      
      numericString = "-30677"
      styles = NumberStyles.None
      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 Short
      Dim result As Boolean = Int16.TryParse(stringToConvert, styles, _
                                             CultureInfo.InvariantCulture, 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 '10677' to 10677.
'       Attempted conversion of '-30677' failed.
'       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 -32575.
'       Attempted conversion of '0x80C1' failed.

注解

Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) 方法与 Int16.Parse(String, NumberStyles, IFormatProvider) 方法的不同之处在于，返回一个布尔值，该值指示分析操作是否成功，而不是返回已分析的 Int16 值。The Int16.TryParse(String, NumberStyles, IFormatProvider, Int16) method differs from the Int16.Parse(String, NumberStyles, IFormatProvider) method by returning a Boolean value that indicates whether the parse operation succeeded instead of returning the parsed Int16 value. 当 s 无效且无法成功分析时，无需使用异常处理来测试 FormatException。It eliminates the need to use exception handling to test for a FormatException in the event that s is invalid and cannot be successfully parsed.

style 参数定义在 s 参数中允许的样式元素（如空格或正号或负号），以便分析操作成功。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. 它必须是 NumberStyles 枚举中的位标志的组合。It must be a combination of bit flags from the NumberStyles enumeration. 根据 style 的值，s 参数可能包含以下元素：Depending on the value of style, the s parameter may include the following elements:

[ws][$][sign][digits,]digits[.fractional_digits][e[sign]digits][ws][ws][$][sign][digits,]digits[.fractional_digits][e[sign]digits][ws]

如果 style 参数包括 NumberStyles.AllowHexSpecifier，则为; 否则为：Or, if the style parameter includes NumberStyles.AllowHexSpecifier:

[ws]hexdigits[ws][ws]hexdigits[ws]

方括号（[和]）中的项是可选的。Items in square brackets ([ and ]) are optional. 下表对每个元素进行了描述。The following table describes each element.

元素Element	说明Description
wsws	可选空白。Optional white space. 如果 style 包含 NumberStyles.AllowLeadingWhite 标志，s 或者如果 style 包含 NumberStyles.AllowTrailingWhite 标志，则空格可以出现在 s 的开头。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.
$	区域性特定的货币符号。A culture-specific currency symbol. 其在字符串中的位置由 provider 参数的 GetFormat 方法返回的 NumberFormatInfo 对象的 CurrencyPositivePattern 属性定义。Its position in the string is defined by the CurrencyPositivePattern property of the NumberFormatInfo object returned by the GetFormat method of the provider parameter. 如果 style 包含 NumberStyles.AllowCurrencySymbol 标志，货币符号可以出现在 s 中。The currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag.
signsign	一个可选的符号。An optional sign.
digitsdigits	介于0到9之间的一系列数字。A sequence of digits from 0 through 9.
，,	区域性特定的千位分隔符。A culture-specific thousands separator. 如果 style 包括 NumberStyles.AllowThousands 标志，则 provider 指定的区域性的千位分隔符可以出现在 s 中。The thousands separator of the culture specified by provider can appear in s if style includes the NumberStyles.AllowThousands flag.
..	区域性特定的小数点符号。A culture-specific decimal point symbol. 如果 style 包括 NumberStyles.AllowDecimalPoint 标志，则 provider 指定的区域性的小数点符号可以出现在 s 中。The decimal point symbol of the culture specified by provider can appear in s if style includes the NumberStyles.AllowDecimalPoint flag.
fractional_digitsfractional_digits	数字0的一个或多个匹配项。One or more occurrences of the digit 0. 仅当 style 包含 NumberStyles.AllowDecimalPoint 标志时，小数位才能出现在 s 中。Fractional digits can appear in s only if style includes the NumberStyles.AllowDecimalPoint flag.
ee	"E" 或 "E" 字符，指示值以指数表示法表示。The 'e' or 'E' character, which indicates that the value is represented in exponential notation. 如果 style 包含 NumberStyles.AllowExponent 标志，则 s 参数可以表示指数表示法中的数字。The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
hexdigitshexdigits	从0到 f 的十六进制数字序列，或者从0到 F。A sequence of hexadecimal digits from 0 through f, or 0 through F.

仅包含十进制数字的字符串（对应于 NumberStyles.None 标志）始终分析成功。A string with decimal digits only (which corresponds to the NumberStyles.None flag) always parses successfully. 大多数其余 NumberStyles 成员控制可能但不要求出现在此输入字符串中的元素。Most of the remaining NumberStyles members control elements that may be but are not required to be present in this input string. 下表指示单个 NumberStyles 成员如何影响可能出现在 s中的元素。The following table indicates how individual NumberStyles members affect the elements that may be present in s.

非复合 NumberStyles 值Non-composite NumberStyles values	除数字外允许在 s 中使用的元素Elements permitted in s in addition to digits
NumberStyles.None	仅十进制数字。Decimal digits only.
NumberStyles.AllowDecimalPoint	.The . 和fractional_digits元素。and fractional_digits elements. 但fractional_digits只能包含一个或多个0位数，否则该方法将返回 false。However, fractional_digits must consist of only one or more 0 digits or the method returns false.
NumberStyles.AllowExponent	s 参数还可以使用指数表示法。The s parameter can also use exponential notation. 如果 s 表示指数表示法中的数字，则它必须表示 Int16 数据类型范围内的一个整数，而不包含非零的小数部分。If s represents a number in exponential notation, it must represent an integer within the range of the Int16 data type without a non-zero fractional component.
NumberStyles.AllowLeadingWhite	开头的ws 元素。The ws element at the beginning of s.
NumberStyles.AllowTrailingWhite	末尾的ws 元素。The ws element at the end of s.
NumberStyles.AllowLeadingSign	符号可以出现在数字之前。A sign can appear before digits.
NumberStyles.AllowTrailingSign	符号可以出现在数字之后。A sign can appear after digits.
NumberStyles.AllowParentheses	用括号括起数值的符号元素。The sign element in the form of parentheses enclosing the numeric value.
NumberStyles.AllowThousands	， 元素。The , element.
NumberStyles.AllowCurrencySymbol	$ 元素。The $ element.
NumberStyles.Currency	所有元素。All elements. S参数不能表示十六进制数或以指数表示法表示的数字。The s parameter cannot represent a hexadecimal number or a number in exponential notation.
NumberStyles.Float	位于 s开头或结尾处的ws元素，在 s的开头处进行签名，并且为 。The ws element at the beginning or end of s, sign at the beginning of s, and the . 符号开头。symbol. s 参数还可以使用指数表示法。The s parameter can also use exponential notation.
NumberStyles.Number	Ws、 sign、千位分隔符（，）和小数点（.）元素。The ws, sign, thousands separator (,), and decimal point (.) elements.
NumberStyles.Any	除 s 之外的所有样式不能表示十六进制数。All styles, except s cannot represent a hexadecimal number.

如果使用 NumberStyles.AllowHexSpecifier 标志，则 s 必须是不带前缀的十六进制值。If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value without a prefix. 例如，"9AF3" 分析成功，但 "0x9AF3" 不能。For example, "9AF3" parses successfully, but "0x9AF3" does not. style 中的唯一其他标志 NumberStyles.AllowLeadingWhite 并 NumberStyles.AllowTrailingWhite。The only other flags that can be present in style are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. （NumberStyles 枚举具有复合样式，NumberStyles.HexNumber，它包含两个空格标志。）(The NumberStyles enumeration has a composite style, NumberStyles.HexNumber, that includes both white space flags.)

provider 参数是一个 IFormatProvider 实现，如 CultureInfo 对象或 NumberFormatInfo 对象，其 GetFormat 方法返回 NumberFormatInfo 对象。The provider parameter is an IFormatProvider implementation, such as a CultureInfo object or a NumberFormatInfo object, whose GetFormat method returns a NumberFormatInfo object. NumberFormatInfo 对象提供有关 s格式的区域性特定信息。The NumberFormatInfo object provides culture-specific information about the format of s. 如果 null``provider，则使用当前区域性的 NumberFormatInfo 对象。If provider is null, the NumberFormatInfo object for the current culture is used.

另请参阅

• Parse
• NumberStyles
• ToString()
• 分析 .NET 中的数字字符串Parsing Numeric Strings in .NET

将指定样式和区域性特定格式的数字的范围表示形式转换为它的等效 16 位带符号整数。Converts the span representation of a number in a specified style and culture-specific format to its 16-bit signed integer equivalent. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded or failed.

public:
 static bool TryParse(ReadOnlySpan<char> s, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] short % result);

public static bool TryParse (ReadOnlySpan<char> s, System.Globalization.NumberStyles style, IFormatProvider provider, out short result);

static member TryParse : ReadOnlySpan<char> * System.Globalization.NumberStyles * IFormatProvider * int16 -> bool

Public Shared Function TryParse (s As ReadOnlySpan(Of Char), style As NumberStyles, provider As IFormatProvider, ByRef result As Short) As Boolean

参数

返回