SByte.TryParse Method (String, NumberStyles, IFormatProvider, SByte%)
Tries to convert the string representation of a number in a specified style and culture-specific format to its SByte equivalent, and returns a value that indicates whether the conversion succeeded.
This API is not CLS-compliant. The CLS-compliant alternative is TryParse(String, Int16). Namespace: System
Assembly: mscorlib (in mscorlib.dll)
[CLSCompliantAttribute(false)] public static bool TryParse( string s, NumberStyles style, IFormatProvider provider, out sbyte result )
- Type: System.String
A string representing a number to convert.
- Type: System.Globalization.NumberStyles
A bitwise combination of enumeration values that indicates the permitted format of s. A typical value to specify is Integer.
- Type: System.IFormatProvider
An object that supplies culture-specific formatting information about s.
- Type: System.SByte%
When this method returns, contains the 8-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 null, is not in a format compliant with style, or represents a number less than MinValue or greater than MaxValue. This parameter is passed uninitialized.
Return ValueType: System.Boolean
true if s was converted successfully; otherwise, false.
The method is like the Parse(String, NumberStyles, IFormatProvider) method, except that it does not throw an exception if the conversion fails. This method eliminates the need to use exception handling to test for a FormatException if value 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 value 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 value parameter may include the following elements:
If the style parameter includes AllowHexSpecifier, the value parameter may include the following elements:
Elements in square brackets ([ and ]) are optional. The following table describes each element.
Optional white space. White space can appear at the start of value if style includes the NumberStyles.AllowLeadingWhite flag, or at the end of value 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 value if style includes the NumberStyles.AllowCurrencySymbol flag.
An optional sign. The sign can appear at the start of value if style includes the NumberStyles.AllowLeadingSign flag, and it can appear at the end of value if style includes the NumberStyles.AllowTrailingSign flag. Parentheses can be used in value to indicate a negative value if style includes the NumberStyles.AllowParentheses flag.
A sequence of digits from 0 through 9.
A culture-specific group separator. The group separator of the culture specified by provider can appear in value 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 value if style includes the NumberStyles.AllowDecimalPoint flag.
One or more occurrences of the digit 0. Fractional digits can appear in value only if style includes the NumberStyles.AllowDecimalPoint flag.
The "e" or "E" character, which indicates that the value is represented in exponential (scientific) notation. The value parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
A sequence of digits from 0 through 9. The value parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
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 flag) always parses successfully. Most of the remaining NumberStyles members control elements that may be present, 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 value.
Non-composite NumberStyles values
Elements permitted in value 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 "e" or "E" character, which indicates exponential notation, along with exponential_digits. If value represents a number in exponential notation, it cannot have a non-zero, fractional component.
The ws element at the start of value.
The ws element at the end of value.
The sign element before digits.
The sign element after digits.
The sign element in the form of parentheses enclosing the numeric value.
The group separator (,) element.
The currency ($) element.
All elements. However, value cannot represent a hexadecimal number or a number in exponential notation.
The ws element at the start or end of value, sign at the start of value, and the decimal point (.) symbol. The value parameter can also use exponential notation.
The ws, sign, group separator (,), and decimal point (.) elements.
All elements. However, value cannot represent a hexadecimal number.
If the NumberStyles.AllowHexSpecifier flag is used, value 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 style, HexNumber, that includes both white-space flags.)
If value is the string representation of a hexadecimal number, it cannot be preceded by any decoration (such as 0x or &h) that differentiates it as a hexadecimal number. This causes the conversion to fail.
The provider parameter is an IFormatProvider implementation. Its GetFormat method returns a NumberFormatInfo object that provides culture-specific information about the format of value. The provider parameter can be any one of the following:
A CultureInfo object that represents the culture that supplies formatting information. Its GetFormat method returns the NumberFormatInfo object that provides numeric formatting information for that culture.
If provider is null, the NumberFormatInfo object for the current culture is used.
The following example calls the method with a number of different string and NumberStyles values.
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.