HashAlgorithm 类

定义

表示所有加密哈希算法实现均必须从中派生的基类。Represents the base class from which all implementations of cryptographic hash algorithms must derive.

public ref class HashAlgorithm abstract : System::Security::Cryptography::ICryptoTransform
[System.Runtime.InteropServices.ComVisible(true)]
public abstract class HashAlgorithm : System.Security.Cryptography.ICryptoTransform
type HashAlgorithm = class
    interface IDisposable
    interface ICryptoTransform
Public MustInherit Class HashAlgorithm
Implements ICryptoTransform
继承
HashAlgorithm
派生
属性
实现

示例

下面的代码示例计算数组SHA1CryptoServiceProvider的哈希值。The following code example computes the SHA1CryptoServiceProvider hash for an array. 此示例假设有一个预定义的字节数组dataArray[]This example assumes that there is a predefined byte array dataArray[]. SHA1CryptoServiceProvider是的HashAlgorithm派生类。SHA1CryptoServiceProvider is a derived class of HashAlgorithm.

HashAlgorithm^ sha = gcnew SHA1CryptoServiceProvider;
array<Byte>^ result = sha->ComputeHash( dataArray );
HashAlgorithm sha = new SHA1CryptoServiceProvider();
byte[] result = sha.ComputeHash(dataArray);
Dim sha As New SHA1CryptoServiceProvider()
Dim result As Byte() = sha.ComputeHash(dataArray)

注解

哈希函数是新式加密的基础。Hash functions are fundamental to modern cryptography. 这些函数将任意长度的二进制字符串映射为固定长度的小型二进制字符串,称为哈希值。These functions map binary strings of an arbitrary length to small binary strings of a fixed length, known as hash values. 加密哈希函数具有属性,该属性不能进行计算以查找两个不同的输入,这些输入将散列到相同的值。A cryptographic hash function has the property that it is computationally infeasible to find two distinct inputs that hash to the same value. 哈希函数通常与数字签名和数据完整性一起使用。Hash functions are commonly used with digital signatures and for data integrity.

哈希值用作表示大量数据的固定大小的唯一值。The hash is used as a unique value of fixed size representing a large amount of data. 如果相应的数据也匹配,则两个数据集的哈希应该匹配。Hashes of two sets of data should match if the corresponding data also matches. 对数据的小更改会导致哈希中的大量无法预测的更改。Small changes to the data result in large unpredictable changes in the hash.

由于 SHA1 出现冲突问题,Microsoft 建议使用基于 SHA256 或更好的安全模型。Due to collision problems with SHA1, Microsoft recommends a security model based on SHA256 or better.

继承者说明

HashAlgorithm类继承时,必须重写以下成员: HashCore(Byte[], Int32, Int32)HashFinal()When you inherit from the HashAlgorithm class, you must override the following members: HashCore(Byte[], Int32, Int32) and HashFinal().

构造函数

HashAlgorithm()

初始化 HashAlgorithm 类的新实例。Initializes a new instance of the HashAlgorithm class.

字段

HashSizeValue

表示计算所得的哈希代码的大小(以位为单位)。Represents the size, in bits, of the computed hash code.

HashValue

表示计算所得的哈希代码的值。Represents the value of the computed hash code.

State

表示哈希计算的状态。Represents the state of the hash computation.

属性

CanReuseTransform

获取一个值,该值指示是否可重复使用当前转换。Gets a value indicating whether the current transform can be reused.

CanTransformMultipleBlocks

当在派生类中重写时,获取一个值,该值指示是否可以转换多个块。When overridden in a derived class, gets a value indicating whether multiple blocks can be transformed.

Hash

获取计算所得的哈希代码的值。Gets the value of the computed hash code.

HashSize

获取计算所得的哈希代码的大小(以位为单位)。Gets the size, in bits, of the computed hash code.

InputBlockSize

当在派生类中重写时,获取输入块的大小。When overridden in a derived class, gets the input block size.

OutputBlockSize

当在派生类中重写时,获取输出块的大小。When overridden in a derived class, gets the output block size.

方法

Clear()

释放 HashAlgorithm 类使用的所有资源。Releases all resources used by the HashAlgorithm class.

ComputeHash(Byte[])

计算指定字节数组的哈希值。Computes the hash value for the specified byte array.

ComputeHash(Byte[], Int32, Int32)

计算指定字节数组的指定区域的哈希值。Computes the hash value for the specified region of the specified byte array.

ComputeHash(Stream)

计算指定 Stream 对象的哈希值。Computes the hash value for the specified Stream object.

Create()

创建哈希算法的默认实现的实例。Creates an instance of the default implementation of a hash algorithm.

Create(String)

创建哈希算法的指定实现的实例。Creates an instance of the specified implementation of a hash algorithm.

Dispose()

释放 HashAlgorithm 类的当前实例所使用的所有资源。Releases all resources used by the current instance of the HashAlgorithm class.

Dispose(Boolean)

释放由 HashAlgorithm 占用的非托管资源,还可以另外再释放托管资源。Releases the unmanaged resources used by the HashAlgorithm and optionally releases the managed resources.

Equals(Object)

确定指定的对象是否等于当前对象。Determines whether the specified object is equal to the current object.

(继承自 Object)
GetHashCode()

作为默认哈希函数。Serves as the default hash function.

(继承自 Object)
GetType()

获取当前实例的 TypeGets the Type of the current instance.

(继承自 Object)
HashCore(Byte[], Int32, Int32)

当在派生类中重写时,将写入对象的数据路由到哈希算法以计算哈希值。When overridden in a derived class, routes data written to the object into the hash algorithm for computing the hash.

HashCore(ReadOnlySpan<Byte>)
HashFinal()

当在派生类中重写时,在加密流对象处理完最后的数据后完成哈希计算。When overridden in a derived class, finalizes the hash computation after the last data is processed by the cryptographic stream object.

Initialize()

初始化 HashAlgorithm 类的实现。Initializes an implementation of the HashAlgorithm class.

MemberwiseClone()

创建当前 Object 的浅表副本。Creates a shallow copy of the current Object.

(继承自 Object)
ToString()

返回表示当前对象的字符串。Returns a string that represents the current object.

(继承自 Object)
TransformBlock(Byte[], Int32, Int32, Byte[], Int32)

计算输入字节数组指定区域的哈希值,并将输入字节数组指定区域复制到输出字节数组的指定区域。Computes the hash value for the specified region of the input byte array and copies the specified region of the input byte array to the specified region of the output byte array.

TransformFinalBlock(Byte[], Int32, Int32)

计算指定字节数组的指定区域的哈希值。Computes the hash value for the specified region of the specified byte array.

TryComputeHash(ReadOnlySpan<Byte>, Span<Byte>, Int32)
TryHashFinal(Span<Byte>, Int32)

显式界面实现

IDisposable.Dispose()

释放由 HashAlgorithm 占用的非托管资源,还可以另外再释放托管资源。Releases the unmanaged resources used by the HashAlgorithm and optionally releases the managed resources.

适用于

另请参阅