C# 0 The Complete Reference

PART II

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633

public static decimal

     Round(decimal 

v

,

                MidPointRounding 

how

)

Returns the value of 

v

 rounded to the nearest whole 

number using the rounding mode specified by 

how.

The rounding mode applies only to those conditions in 

which

v

 is at the midpoint between two whole numbers. 

public static decimal

     Round(decimal 

v

, int 

decPlaces

,

                MidPointRounding 

how

)

Returns the value of 

v

 rounded to the number of 

decimal places specified by 

decPlaces

(which must be 

between 0 and 28), using the rounding mode specified 

by

how

. The rounding mode applies only to those 

conditions in which 

v

 is at the midpoint between two 

rounded values. 

public static decimal

    Subtract(decimal 

v1

, decimal 

v2

)

Returns 

v1

–

v2.

public static byte ToByte(decimal 

v

)

Returns the 

byte

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of a 

byte

.

public static double ToDouble(decimal 

v

)

Returns the 

double

 equivalent of 

v.

 A loss of precision 

may occur because 

double

 has fewer significant digits 

than does 

decimal

.

public static shor t ToInt16(decimal 

v

)

Returns the 

short

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of a 

short

.

public static int ToInt32(decimal 

v

)

Returns the 

int

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of an 

int

.

public static long ToInt64(decimal 

v

)

Returns the 

long

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of a 

long

.

public static long

     ToOACurrency(decimal 

v

)

Conver ts 

v

 into the equivalent OLE Automation 

currency value and returns the result.

public static sbyte ToSByte(decimal 

v

)

Returns the 

sbyte

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of an 

sbyte

.

public static float ToSingle(decimal 

v

)

Returns the 

float

 equivalent of 

v.

 A loss of precision 

may occur because 

float

 has fewer significant digits 

than does 

decimal

.

public override string ToString( )

Returns the string representation of the value of the 

invoking object in the default format.

public string ToString(string 

format

)

Returns the string representation of the value of 

the invoking object as specified by the format string 

passed in 

format.

Method

Meaning

T

ABLE

 21-7 

Methods Defi ned by 

Decimal

(continued)

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Char

The structure corresponding to the 

char

 type is 

Char

. It is quite useful because it supplies a 

large number of methods that allow you to process and categorize characters. For example, 

you can convert a lowercase character to uppercase by calling 

ToUpper( )

. You can determine 

if a character is a digit by calling 

IsDigit( )

.

The methods defined by 

Char

 are shown in Table 21-9. Notice that several, such as 

ConvertFromUtf32( ) 

and

ConvertToUtf32( )

, give you the ability to work with both UTF-16 

and UTF-32 Unicode characters. In the past, all Unicode characters could be represented by 

16 bits, which is the size of a 

char

. However, a few years ago the Unicode character set was 

expanded and more than 16 bits are required. Each Unicode character is represented by a 

code point.

 The way that a code point is encoded depends on the Unicode Transformation 

Format (UTF) being used. In UTF-16, the most common code points require one 16-bit 

value, but some need two 16-bit values. When two 16-bit values are needed, two 

char

public string

     ToString(IFormatProvider 

fmtpvdr

)

Returns the string representation of the value of the 

invoking object using the culture-specific information 

specified in 

fmtpvdr.

public string

     ToString(string 

format

,

                 IFormatProvider 

fmtpvdr

)

Returns the string representation of the value of the 

invoking object using the culture-specific information 

specified in 

fmtpvdr

 and the format specified by 

format.

public static ushor t ToUInt16(decimal 

v

)

Returns the 

ushort

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of a 

ushort

.

public static uint ToUInt32(decimal 

v

)

Returns the 

uint

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of a 

uint

.

public static ulong ToUInt64(decimal 

v

)

Returns the 

ulong

 equivalent of 

v.

 Any fractional 

component is truncated. An 

OverflowException

 occurs 

if

v

 is not within the range of a 

ulong

.

public static decimal Truncate(decimal 

v

)

Returns the whole-number por tion of 

v.

 Thus, it 

truncates any fractional digits.

public static bool

     Tr yParse(string 

str

, out decimal

 val

)

Attempts to conver t the numeric string in 

str

 into a 

decimal

 value. If successful, the value is stored in 

val

 and true is returned. If no conversion takes place, 

false is returned. This differs from 

Parse( )

, which 

throws an exception on failure. 

public static bool Tr yParse(string 

str

,

                          NumberStyles 

styles

,

IFormatProvider 

fmtpvdr

,

                          out decimal 

val

)

Attempts to conver t the numeric string in 

str

 into a 

decimal

 value using the style information provided 

by

styles

 and the culture-specific format information 

provided by 

fmtpvdr.

 If successful, the value is stored 

in

val

 and true is returned. If no conversion takes 

place, false is returned. This differs from 

Parse( )

,

which throws an exception on failure. 

T

ABLE

 21-7 

Methods Defi ned by 

Decimal

(continued)

Method

Meaning

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