WorkbookBase.PasswordEncryptionKeyLength Property

public:
 property int PasswordEncryptionKeyLength { int get(); };

public int PasswordEncryptionKeyLength { get; }

member this.PasswordEncryptionKeyLength : int

Public ReadOnly Property PasswordEncryptionKeyLength As Integer

Property Value

The key length of the algorithm that Excel uses when encrypting passwords for the workbook.

Examples

The following code example checks the value of the HasPassword property to determine whether the workbook is password protected. If the workbook is not password protected, then the example sets the Password property to a password obtained from user input, and then calls the SetPasswordEncryptionOptions method to set the encryption algorithm, set the key length, set the name of the encryption provider, and enable file property encryption. The example then displays the values of the PasswordEncryptionProvider, PasswordEncryptionAlgorithm, PasswordEncryptionKeyLength, and PasswordEncryptionFileProperties properties in worksheet Sheet1. This example assumes that the method GetPasswordFromUserInput is defined elsewhere.

This example is for a document-level customization.

private void WorkbookPasswordOptions()
{
    if (!this.HasPassword)
    {
        this.Password = GetPasswordFromUserInput();
        this.SetPasswordEncryptionOptions(
            "Microsoft RSA SChannel Cryptographic Provider",
            "RC4", 128, true);
    }

    // Display the password properties in Sheet1.
    Globals.Sheet1.Range["A1"].Value2 =
        "Password Encryption Provider:";
    Globals.Sheet1.Range["A2"].Value2 =
        "Password Encryption Algorithm:";
    Globals.Sheet1.Range["A3"].Value2 =
        "Password Encryption Key Length:";
    Globals.Sheet1.Range["A4"].Value2 =
        "Password Encryption File Properties:";
    Globals.Sheet1.Range["A1", "A4"].Columns.AutoFit();

    Globals.Sheet1.Range["B1"].Value2 =
        this.PasswordEncryptionProvider;
    Globals.Sheet1.Range["B2"].Value2 =
        this.PasswordEncryptionAlgorithm;
    Globals.Sheet1.Range["B3"].Value2 =
        this.PasswordEncryptionKeyLength;
    Globals.Sheet1.Range["B4"].Value2 =
        this.PasswordEncryptionFileProperties;
    Globals.Sheet1.Range["B1", "B4"].Columns.AutoFit();
}

Private Sub WorkbookPasswordOptions()
    If Not Me.HasPassword Then
        Me.Password = GetPasswordFromUserInput()
        Me.SetPasswordEncryptionOptions( _
            "Microsoft RSA SChannel Cryptographic Provider", _
            "RC4", 128, True)
    End If

    ' Display the password properties in Sheet1.
    Globals.Sheet1.Range("A1").Value2 = _
        "Password Encryption Provider:"
    Globals.Sheet1.Range("A2").Value2 = _
        "Password Encryption Algorithm:"
    Globals.Sheet1.Range("A3").Value2 = _
        "Password Encryption Key Length:"
    Globals.Sheet1.Range("A4").Value2 = _
        "Password Encryption File Properties:"
    Globals.Sheet1.Range("A1", "A4").Columns.AutoFit()

    Globals.Sheet1.Range("B1").Value2 = _
        Me.PasswordEncryptionProvider
    Globals.Sheet1.Range("B2").Value2 = _
        Me.PasswordEncryptionAlgorithm
    Globals.Sheet1.Range("B3").Value2 = _
        Me.PasswordEncryptionKeyLength
    Globals.Sheet1.Range("B4").Value2 = _
        Me.PasswordEncryptionFileProperties
    Globals.Sheet1.Range("B1", "B4").Columns.AutoFit()
End Sub

Remarks

Use the SetPasswordEncryptionOptions method to specify whether Excel encrypts file properties for the specified password-protected workbook.

Applies to