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ToUInt32 Method (String, Int32)

Convert::ToUInt32 Method (String, Int32)

Converts the string representation of a number in a specified base to an equivalent 32-bit unsigned integer.

This API is not CLS-compliant. 

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

[CLSCompliantAttribute(false)]
public:
static unsigned int ToUInt32(
	String^ value, 
	int fromBase
)

Parameters

value
Type: System::String

A string that contains the number to convert.

fromBase
Type: System::Int32

The base of the number in value, which must be 2, 8, 10, or 16.

Return Value

Type: System::UInt32
A 32-bit unsigned integer that is equivalent to the number in value, or 0 (zero) if value is nullptr.

ExceptionCondition
ArgumentException

fromBase is not 2, 8, 10, or 16.

-or-

value, which represents a non-base 10 unsigned number, is prefixed with a negative sign.

FormatException

value contains a character that is not a valid digit in the base specified by fromBase. The exception message indicates that there are no digits to convert if the first character in value is invalid; otherwise, the message indicates that value contains invalid trailing characters.

OverflowException

value, which represents a non-base 10 unsigned number, is prefixed with a negative sign.

-or-

value represents a number that is less than UInt32::MinValue or greater than UInt32::MaxValue.

If fromBase is 16, you can prefix the number specified by the value parameter with "0x" or "0X".

Because the UInt32 data type supports unsigned values only, the ToUInt32(String, Int32) method assumes that value is expressed using unsigned binary representation. In other words, all 32 bits are used to represent the numeric value, and a sign bit is absent. As a result, it is possible to write code in which a signed integer value that is out of the range of the UInt32 data type is converted to a UInt32 value without the method throwing an exception. The following example converts MinValue to its hexadecimal string representation, and then calls the ToUInt32(String, Int32) method. Instead of throwing an exception, the method displays the message, "0x80000000 converts to 2147483648."

No code example is currently available or this language may not be supported.

When performing binary operations or numeric conversions, it is always the responsibility of the developer to verify that a method or operator is using the appropriate numeric representation to interpret a particular value. The following example illustrates one technique for ensuring that the method does not inappropriately use binary representation to interpret a value that uses two's complement representation when converting a hexadecimal string to a UInt32 value. The example determines whether a value represents a signed or an unsigned integer while it is converting that value to its string representation. When the example converts the value to a UInt32 value, it checks whether the original value was a signed integer. If so, and if its high-order bit is set (which indicates that the original value was negative), the method throws an exception.

No code example is currently available or this language may not be supported.

The following example attempts to interpret each element in an array of numeric strings as a hexadecimal value and to convert it to an unsigned integer.

No code example is currently available or this language may not be supported.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

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