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Int32 Structure

Represents a 32-bit signed integer.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

[ComVisibleAttribute(true)]
public struct Int32 : IComparable, IFormattable, 
	IConvertible, IComparable<int>, IEquatable<int>

The Int32 type exposes the following members.

  NameDescription
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360CompareTo(Int32)Compares this instance to a specified 32-bit signed integer and returns an integer that indicates whether the value of this instance is greater than, less than, or equal to the value of the specified 32-bit signed integer.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360CompareTo(Object)Compares this instance to a specified object and returns an integer that indicates whether the value of this instance is greater than, less than, or equal to the value of the specified object.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360Equals(Int32)Returns a value indicating whether this instance is equal to a specified Int32 value.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360Equals(Object)Returns a value indicating whether this instance is equal to a specified object. (Overrides ValueType.Equals(Object).)
Protected methodSupported by Silverlight for Windows PhoneSupported by Xbox 360FinalizeAllows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360GetHashCodeReturns the hash code for this instance. (Overrides ValueType.GetHashCode().)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360GetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360GetTypeCodeReturns the TypeCode for value type Int32.
Protected methodSupported by Silverlight for Windows PhoneSupported by Xbox 360MemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360Parse(String)Converts the string representation of a number to its 32-bit signed integer equivalent.
Public methodStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360Parse(String, NumberStyles)Converts the string representation of a number in a specified style to its 32-bit signed integer equivalent.
Public methodStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360Parse(String, IFormatProvider)Converts the string representation of a number in a specified culture-specific format to its 32-bit signed integer equivalent.
Public methodStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360Parse(String, NumberStyles, IFormatProvider)Converts the string representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360ToString()Converts the numeric value of this instance to its equivalent string representation. (Overrides ValueType.ToString().)
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360ToString(IFormatProvider)Converts the numeric value of this instance to its equivalent string representation using the specified culture-specific format information.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360ToString(String)Converts the numeric value of this instance to its equivalent string representation, using the specified format.
Public methodSupported by Silverlight for Windows PhoneSupported by Xbox 360ToString(String, IFormatProvider)Converts the numeric value of this instance to its equivalent string representation using the specified format and culture-specific format information.
Public methodStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360TryParse(String, Int32)Converts the string representation of a number to its 32-bit signed integer equivalent. A return value indicates whether the conversion succeeded.
Public methodStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360TryParse(String, NumberStyles, IFormatProvider, Int32)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.
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  NameDescription
Public fieldStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360MaxValueRepresents the largest possible value of an Int32. This field is constant.
Public fieldStatic memberSupported by Silverlight for Windows PhoneSupported by Xbox 360MinValueRepresents the smallest possible value of Int32. This field is constant.
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  NameDescription
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToBooleanInfrastructure. For a description of this member, see IConvertible.ToBoolean.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToByteInfrastructure. For a description of this member, see IConvertible.ToByte.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToCharInfrastructure. For a description of this member, see IConvertible.ToChar.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToDateTimeInfrastructure. This conversion is not supported. Attempting to use this method throws an InvalidCastException.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToDecimalInfrastructure. For a description of this member, see IConvertible.ToDecimal.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToDoubleInfrastructure. For a description of this member, see IConvertible.ToDouble.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToInt16Infrastructure. For a description of this member, see IConvertible.ToInt16.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToInt32Infrastructure. For a description of this member, see IConvertible.ToInt32.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToInt64Infrastructure. For a description of this member, see IConvertible.ToInt64.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToSByteInfrastructure. For a description of this member, see IConvertible.ToSByte.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToSingleInfrastructure. For a description of this member, see IConvertible.ToSingle.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToTypeInfrastructure. For a description of this member, see IConvertible.ToType.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToUInt16Infrastructure. For a description of this member, see IConvertible.ToUInt16.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToUInt32Infrastructure. For a description of this member, see IConvertible.ToUInt32.
Explicit interface implemetationPrivate methodSupported by Silverlight for Windows PhoneSupported by Xbox 360IConvertible.ToUInt64Infrastructure. For a description of this member, see IConvertible.ToUInt64.
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Int32 is an immutable value type that represents signed integers with values that range from negative 2,147,483,648 (which is represented by the Int32.MinValue constant) through positive 2,147,483,647 (which is represented by the Int32.MaxValue constant. The .NET Framework also includes an unsigned 32-bit integer value type, UInt32, which represents values that range from 0 to 4,294,967,295.

Instantiating an Int32 Value

You can instantiate an Int32 value in several ways:

  • You can declare an Int32 variable and assign it a literal integer value that is within the range of the Int32 data type. The following example declares two Int32 variables and assigns them values in this way.

    
    int number1 = 64301;
    int number2 = 25548612;
    
    
    
  • You can assign the value of an integer type whose range is a subset of the Int32 type. This is a widening conversion that does not require a cast operator in C# or a conversion method in Visual Basic.

    
    sbyte value1 = 124;
    short value2 = 1618;
    
    int number1 = value1;
    int number2 = value2;
    
    
    
  • You can assign the value of a numeric type whose range exceeds that of the Int32 type. This is a narrowing conversion, so it requires a cast operator in C# and a conversion method in Visual Basic if Option Strict is on. If the numeric value is a Single, Double, or Decimal value that includes a fractional component, the handling of its fractional part depends on the compiler performing the conversion. The following example performs narrowing conversions to assign several numeric values to Int32 variables.

    
    long lNumber = 163245617;
    try
    {
       int number1 = (int)lNumber;
       outputBlock.Text += number1 + "\n";
    }
    catch (OverflowException)
    {
       outputBlock.Text += String.Format("{0} is out of range of an Int32.", lNumber) + "\n";
    }
    
    double dbl2 = 35901.997;
    try
    {
       int number2 = (int)dbl2;
       outputBlock.Text += number2 + "\n";
    }
    catch (OverflowException)
    {
       outputBlock.Text += String.Format("{0} is out of range of an Int32.", dbl2) + "\n";
    }
    
    BigInteger bigNumber = 132451;
    try
    {
       int number3 = (int)bigNumber;
       outputBlock.Text += number3 + "\n";
    }
    catch (OverflowException)
    {
       outputBlock.Text += String.Format("{0} is out of range of an Int32.", bigNumber) + "\n";
    }
    // The example displays the following output:
    //       163245617
    //       35902
    //       132451
    
    
    
  • You can call a method of the Convert class to convert any supported type to an Int32 value. This is possible because Int32 supports the IConvertible interface. The following example illustrates the conversion of an array of Decimal values to Int32 values.

  • You can call the Parse or TryParse method to convert the string representation of an Int32 value to an Int32. The string can contain either decimal or hexadecimal digits. The following example illustrates the parse operation by using both a decimal and a hexadecimal string.

    
    string string1 = "244681";
    try
    {
       int number1 = Int32.Parse(string1);
       outputBlock.Text += number1 + "\n";
    }
    catch (OverflowException)
    {
       outputBlock.Text += String.Format("'{0}' is out of range of a 32-bit integer.", string1) + "\n";
    }
    catch (FormatException)
    {
       outputBlock.Text += String.Format("The format of '{0}' is invalid.", string1) + "\n";
    }
    
    string string2 = "F9A3C";
    try
    {
       int number2 = Int32.Parse(string2,
                                System.Globalization.NumberStyles.HexNumber);
       outputBlock.Text += number2 + "\n";
    }
    catch (OverflowException)
    {
       outputBlock.Text += String.Format("'{0}' is out of range of a 32-bit integer.", string2) + "\n";
    }
    catch (FormatException)
    {
       outputBlock.Text += String.Format("The format of '{0}' is invalid.", string2) + "\n";
    }
    // The example displays the following output:
    //       244681
    //       1022524
    
    
    

Performing Operations on Int32 Values

The Int32 type supports standard mathematical operations such as addition, subtraction, division, multiplication, subtraction, negation, and unary negation. Like the other integral types, the Int32 type also supports the bitwise AND, OR, XOR, left shift, and right shift operators.

You can use the standard numeric operators to compare two Int32 values, or you can call the CompareTo or Equals method.

Representing an Int32 as a String

The Int32 type provides full support for standard and custom numeric format strings. (For more information, see Formatting Types, Standard Numeric Format Strings, and Custom Numeric Format Strings.)

To format an Int32 value as an integral string with no leading zeros, you can call the parameterless ToString() method. By using the "D" format specifier, you can also include a specified number of leading zeros in the string representation. By using the "N" format specifier, you can include group separators and specify the number of decimal digits to appear in the string representation of the number. By using the "X" format specifier, you can represent an Int32 value as a hexadecimal string. The following example formats the elements in an array of Int32 values in these four ways.


int[] numbers = { -1403, 0, 169, 1483104 };
foreach (int number in numbers)
{
   // Display value using default formatting.
   outputBlock.Text += String.Format("{0,-8}  -->   ", number.ToString());
   // Display value with 3 digits and leading zeros.
   outputBlock.Text += String.Format("{0,11:D3}", number);
   // Display value with 1 decimal digit.
   outputBlock.Text += String.Format("{0,13:N1}", number);
   // Display value as hexadecimal.
   outputBlock.Text += String.Format("{0,12:X2}", number);
   // Display value with eight hexadecimal digits.
   outputBlock.Text += String.Format("{0,14:X8}", number) + "\n";
}
// The example displays the following output:
//    -1403     -->         -1403     -1,403.0    FFFFFA85      FFFFFA85
//    0         -->           000          0.0          00      00000000
//    169       -->           169        169.0          A9      000000A9
//    1483104   -->       1483104  1,483,104.0      16A160      0016A160


You can also format an Int32 value as a binary, octal, decimal, or hexadecimal string by calling the ToString(Int32, Int32) method and supplying the base as the method's second parameter. The following example calls this method to display the binary, octal, and hexadecimal representations of an array of integer values.


int[] numbers = { -146, 11043, 2781913 };
outputBlock.Text += String.Format("{0,8}   {1,32}   {2,11}   {3,10}",
                  "Value", "Binary", "Octal", "Hex") + "\n";
foreach (int number in numbers)
{
   outputBlock.Text += String.Format("{0,8}   {1,32}   {2,11}   {3,10}",
                     number, Convert.ToString(number, 2),
                     Convert.ToString(number, 8),
                     Convert.ToString(number, 16)) + "\n";
}
// The example displays the following output:
//       Value                             Binary         Octal          Hex
//        -146   11111111111111111111111101101110   37777777556     ffffff6e
//       11043                     10101100100011         25443         2b23
//     2781913             1010100111001011011001      12471331       2a72d9


Working with Non-Decimal 32-Bit Integer Values

In addition to working with individual integers as decimal values, you may want to perform bitwise operations with integer values, or work with the binary or hexadecimal representations of integer values. Int32 values are represented in 31 bits, with the thirty-second bit used as a sign bit. Positive values are represented by using sign-and-magnitude representation. Negative values are in two's complement representation. This is important to keep in mind when you perform bitwise operations on Int32 values or when you work with individual bits. In order to perform a numeric, Boolean, or comparison operation on any two non-decimal values, both values must use the same representation.

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

All members of this type are thread safe. Members that appear to modify instance state actually return a new instance initialized with the new value. As with any other type, reading and writing to a shared variable that contains an instance of this type must be protected by a lock to guarantee thread safety.

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