HashAlgorithm.Create Method

Definition

Namespace:

System.Security.Cryptography

Assemblies:

netstandard.dll, System.Security.Cryptography.dll

Creates an instance of an implementation of a hash algorithm.

Overloads

Create()	Obsolete. Creates an instance of the default implementation of a hash algorithm.
Create(String)	Obsolete. Creates an instance of the specified implementation of a hash algorithm.

Create()

Source:

HashAlgorithm.cs

Caution

The default implementation of this cryptography algorithm is not supported.

Creates an instance of the default implementation of a hash algorithm.

C#

[System.Obsolete("The default implementation of this cryptography algorithm is not supported.", DiagnosticId="SYSLIB0007", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
public static System.Security.Cryptography.HashAlgorithm Create();

Returns

HashAlgorithm

A new SHA1CryptoServiceProvider instance, unless the default settings have been changed using the .

Attributes

ObsoleteAttribute

Exceptions

PlatformNotSupportedException

.NET Core 2.0 - 3.1 and .NET 5 and later: In all cases.

Remarks

This method is obsolete in .NET 5 and later versions.

By default, this overload uses the SHA1CryptoServiceProvider implementation of a hash algorithm. If you want to specify a different implementation, use the Create(String) overload, which lets you specify an algorithm name, instead. The cryptography configuration system defines the default implementation of HashAlgorithm.

Due to collision problems with SHA1, Microsoft recommends a security model based on SHA256 or better.

Create(String)

Source:

HashAlgorithm.cs

Caution

Cryptographic factory methods accepting an algorithm name are obsolete. Use the parameterless Create factory method on the algorithm type instead.

Creates an instance of the specified implementation of a hash algorithm.

C#

[System.Obsolete("Cryptographic factory methods accepting an algorithm name are obsolete. Use the parameterless Create factory method on the algorithm type instead.", DiagnosticId="SYSLIB0045", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
public static System.Security.Cryptography.HashAlgorithm? Create(string hashName);

Parameters

hashName

String

The hash algorithm implementation to use. The following table shows the valid values for the hashName parameter and the algorithms they map to.

Parameter value	Implements
SHA	SHA1CryptoServiceProvider
SHA1	SHA1CryptoServiceProvider
System.Security.Cryptography.SHA1	SHA1CryptoServiceProvider
System.Security.Cryptography.HashAlgorithm	SHA1CryptoServiceProvider
MD5	MD5CryptoServiceProvider
System.Security.Cryptography.MD5	MD5CryptoServiceProvider
SHA256	SHA256Managed
SHA-256	SHA256Managed
System.Security.Cryptography.SHA256	SHA256Managed
SHA384	SHA384Managed
SHA-384	SHA384Managed
System.Security.Cryptography.SHA384	SHA384Managed
SHA512	SHA512Managed
SHA-512	SHA512Managed
System.Security.Cryptography.SHA512	SHA512Managed

Returns

HashAlgorithm

A new instance of the specified hash algorithm, or null if hashName is not a valid hash algorithm.

Attributes

ObsoleteAttribute