RequiresZip64 Property

DotNetZip

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Ionic Zip Library v1.9.1.6 RequiresZip64 Property

Indicates whether the archive requires ZIP64 extensions.

Declaration Syntax

Visual Basic

Visual C++

public Nullable<bool> RequiresZip64 { get; }

Public ReadOnly Property RequiresZip64 As Nullable(Of Boolean)
	Get

public:
property Nullable<bool> RequiresZip64 {
	Nullable<bool> get ();
}

Remarks

This property is null (or Nothing in VB) if the archive has not been saved, and there are fewer than 65334 ZipEntry items contained in the archive.

The Value is true if any of the following four conditions holds: the uncompressed size of any entry is larger than 0xFFFFFFFF; the compressed size of any entry is larger than 0xFFFFFFFF; the relative offset of any entry within the zip archive is larger than 0xFFFFFFFF; or there are more than 65534 entries in the archive. (0xFFFFFFFF = 4,294,967,295). The result may not be known until a Save() is attempted on the zip archive. The Value of this Nullable property may be set only AFTER one of the Save() methods has been called.

If none of the four conditions holds, and the archive has been saved, then the Value is false.

A Value of false does not indicate that the zip archive, as saved, does not use ZIP64. It merely indicates that ZIP64 is not required. An archive may use ZIP64 even when not required if the UseZip64WhenSaving property is set to Always, or if the UseZip64WhenSaving property is set to AsNecessary and the output stream was not seekable. Use the OutputUsedZip64 property to determine if the most recent Save() method resulted in an archive that utilized the ZIP64 extensions.