/// <summary>
/// Checks a file to see if it is a valid zip file.
/// </summary>
///
/// <remarks>
/// <para>
/// This method opens the specified zip file, reads in the zip archive,
/// verifying the ZIP metadata as it reads.
/// </para>
///
/// <para>
/// If everything succeeds, then the method returns true. If anything fails -
/// for example if an incorrect signature or CRC is found, indicating a
/// corrupt file, the the method returns false. This method also returns
/// false for a file that does not exist.
/// </para>
///
/// <para>
/// If <paramref name="testExtract"/> is true, as part of its check, this
/// method reads in the content for each entry, expands it, and checks CRCs.
/// This provides an additional check beyond verifying the zip header and
/// directory data.
/// </para>
///
/// <para>
/// If <paramref name="testExtract"/> is true, and if any of the zip entries
/// are protected with a password, this method will return false. If you want
/// to verify a <c>ZipFile</c> that has entries which are protected with a
/// password, you will need to do that manually.
/// </para>
///
/// </remarks>
///
/// <param name="zipFileName">The zip file to check.</param>
/// <param name="testExtract">true if the caller wants to extract each entry.</param>
/// <returns>true if the file contains a valid zip file.</returns>
public static bool IsZipFile(string zipFileName, bool testExtract)
{
return(ZipFileExtensions.IsZipFile(zipFileName, testExtract));
}
/// <summary>
/// Checks the given file to see if it appears to be a valid zip file.
/// </summary>
/// <remarks>
///
/// <para>
/// Calling this method is equivalent to calling <see cref="IsZipFile(string,
/// bool)"/> with the testExtract parameter set to false.
/// </para>
/// </remarks>
///
/// <param name="zipFileName">The file to check.</param>
/// <returns>true if the file appears to be a zip file.</returns>
public static bool IsZipFile(string zipFileName)
{
return(ZipFileExtensions.IsZipFile(zipFileName));
}