Function Open( _
	<InAttribute()> ByVal Filename As String, _
	<InAttribute()> Optional ByVal UpdateLinks As Object, _
	<InAttribute()> Optional ByVal ReadOnly As Object, _
	<InAttribute()> Optional ByVal Format As Object, _
	<InAttribute()> Optional ByVal Password As Object, _
	<InAttribute()> Optional ByVal WriteResPassword As Object, _
	<InAttribute()> Optional ByVal IgnoreReadOnlyRecommended As Object, _
	<InAttribute()> Optional ByVal Origin As Object, _
	<InAttribute()> Optional ByVal Delimiter As Object, _
	<InAttribute()> Optional ByVal Editable As Object, _
	<InAttribute()> Optional ByVal Notify As Object, _
	<InAttribute()> Optional ByVal Converter As Object, _
	<InAttribute()> Optional ByVal AddToMru As Object, _
	<InAttribute()> Optional ByVal Local As Object, _
	<InAttribute()> Optional ByVal CorruptLoad As Object _
) As Workbook

Workbook Open(
	[In] string Filename, 
	[In, Optional] object UpdateLinks, 
	[In, Optional] object ReadOnly, 
	[In, Optional] object Format, 
	[In, Optional] object Password, 
	[In, Optional] object WriteResPassword, 
	[In, Optional] object IgnoreReadOnlyRecommended, 
	[In, Optional] object Origin, 
	[In, Optional] object Delimiter, 
	[In, Optional] object Editable, 
	[In, Optional] object Notify, 
	[In, Optional] object Converter, 
	[In, Optional] object AddToMru, 
	[In, Optional] object Local, 
	[In, Optional] object CorruptLoad
);

public: Workbook^ Open(
	String^ Filename, 
	Object^ UpdateLinks, 
	Object^ ReadOnly, 
	Object^ Format, 
	Object^ Password, 
	Object^ WriteResPassword, 
	Object^ IgnoreReadOnlyRecommended, 
	Object^ Origin, 
	Object^ Delimiter, 
	Object^ Editable, 
	Object^ Notify, 
	Object^ Converter, 
	Object^ AddToMru, 
	Object^ Local, 
	Object^ CorruptLoad
);

public Workbook Open(
	/*in*/System.String Filename, 
	/*in*/System.Object UpdateLinks, 
	/*in*/System.Object ReadOnly, 
	/*in*/System.Object Format, 
	/*in*/System.Object Password, 
	/*in*/System.Object WriteResPassword, 
	/*in*/System.Object IgnoreReadOnlyRecommended, 
	/*in*/System.Object Origin, 
	/*in*/System.Object Delimiter, 
	/*in*/System.Object Editable, 
	/*in*/System.Object Notify, 
	/*in*/System.Object Converter, 
	/*in*/System.Object AddToMru, 
	/*in*/System.Object Local, 
	/*in*/System.Object CorruptLoad
);

function Open(
	 Filename : String, 
	 UpdateLinks : Object, 
	 ReadOnly : Object, 
	 Format : Object, 
	 Password : Object, 
	 WriteResPassword : Object, 
	 IgnoreReadOnlyRecommended : Object, 
	 Origin : Object, 
	 Delimiter : Object, 
	 Editable : Object, 
	 Notify : Object, 
	 Converter : Object, 
	 AddToMru : Object, 
	 Local : Object, 
	 CorruptLoad : Object
) : Workbook;

Parameters

Filename

Required String. The file name of the workbook to be opened.

UpdateLinks

Optional Object. Specifies the way links in the file are updated. If this argument is omitted, the user is prompted to specify how links will be updated. Otherwise, this argument is one of the values listed in the following table.

Value	Meaning
1	User specifies how links will be updated
2	Never update links for this workbook on opening
3	Always update links for this workbook on opening

If Microsoft Excel is opening a file in the WKS, WK1, or WK3 format and the UpdateLinks argument is 2, Microsoft Excel generates charts from the graphs attached to the file. If the argument is 0, no charts are created.

ReadOnly

Optional Object. True to open the workbook in read-only mode.

Format

Optional Object. If Microsoft Excel is opening a text file, this argument specifies the delimiter character, as shown in the following table. If this argument is omitted, the current delimiter is used.

Value	Delimiter
1	Tabs
2	Commas
3	Spaces
4	Semicolons
5	Nothing
6	Custom character (see the Delimiter argument)

Password

Optional Object. A string that contains the password required to open a protected workbook. If this argument is omitted and the workbook requires a password, the user is prompted for the password.

WriteResPassword

Optional Object. A string that contains the password required to write to a write-reserved workbook. If this argument is omitted and the workbook requires a password, the user will be prompted for the password.

IgnoreReadOnlyRecommended

Optional Object. True to have Microsoft Excel not display the read-only recommended message (if the workbook was saved with the Read-Only Recommended option).

Origin

Optional Object. If the file is a text file, this argument indicates where it originated (so that code pages and Carriage Return/Line Feed (CR/LF) can be mapped correctly). Can be one of the following XlPlatform constants: xlMacintosh, xlWindows, or xlMSDOS. If this argument is omitted, the current operating system is used.

Delimiter

Optional Object. If the file is a text file and the Format argument is 6, this argument is a string that specifies the character to be used as the delimiter. For example, use Chr(9) for tabs, use "," for commas, use ";" for semicolons, or use a custom character. Only the first character of the string is used.

Editable

Optional Object. If the file is a Microsoft Excel 4.0 add-in, this argument is True to open the add-in so that it’s a visible window. If this argument is False or omitted, the add-in is opened as hidden, and it cannot be unhidden. This option doesn't apply to add-ins created in Microsoft Excel 5.0 or later. If the file is an Excel template, use True to open the specified template for editing or False to open a new workbook based on the specified template. The default value is False.

Notify

Optional Object. If the file cannot be opened in read/write mode, this argument is True to add the file to the file notification list. Microsoft Excel will open the file as read-only, poll the file notification list, and then notify the user when the file becomes available. If this argument is False or omitted, no notification is requested, and any attempts to open an unavailable file will fail.

Converter

Optional Object. The index of the first file converter to try when opening the file. The specified file converter is tried first; if this converter doesn’t recognize the file, all other converters are tried. The converter index consists of the row numbers of the converters returned by the FileConverters property.

AddToMru

Optional Object. True to add this workbook to the list of recently used files. The default value is False.

Local

Optional Object. True saves files against the language of Microsoft Excel (including control panel settings). False (default) saves files against the language of Visual Basic for Applications (VBA) (which is typically U.S. English unless the VBA project where Workbooks.Open is run from is an old internationalized XL5/95 VBA project).

CorruptLoad

Optional Object. Can be one of the following constants: xlNormalLoad, xlRepairFile, and xlExtractData. The default behavior if no value is specified is usually normal, but may be safe load or data recovery if Excel has already attempted to open the file. The first attempt is normal. If Excel stops operating while opening the file, the second attempt is safe load. If Excel again stops operating, the next attempt is data recovery.