/// <summary>创建加密哈希算法的默认实现的实例。</summary>
/// <returns>新 <see cref="T:System.Security.Cryptography.HMACSHA1" /> 实例,除非已更改默认设置。</returns>
/// <PermissionSet>
/// <IPermission class="System.Security.Permissions.SecurityPermission, mscorlib, Version=2.0.3600.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" version="1" Flags="UnmanagedCode" />
/// </PermissionSet>
public static KeyedHashAlgorithm Create()
{
return(KeyedHashAlgorithm.Create("System.Security.Cryptography.KeyedHashAlgorithm"));
}