VB编程用DAO访问数据对象时，求教Bookmark属性
调试时，bookmark属性下有四个值，分别是：bookmark（0），bookmark（1），bookmark（2），bookmark（3）。它们分别代表什么意思？
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记录集中书签可以设置多个，它们分别代表一条记录在记录集中的位置。－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－－
Bookmark Property
Sets or returns a bookmark that uniquely identifies the current record in a Recordset object.
Settings and Return Values
The setting or return value is a string expression or variant expression that evaluates to a valid bookmark. The data type is a Variant array of Byte data.
Remarks
For a Recordset object based entirely on Microsoft Jet tables, the value of the Bookmarkable property is True, and you can use the Bookmark property with that Recordset. Other database products may not support bookmarks, however. For example, you can't use bookmarks in any Recordset object based on a linked Paradox table that has no primary key.
When you create or open a Recordset object, each of its records already has a unique bookmark. You can save the bookmark for the current record by assigning the value of the Bookmark property to a variable. To quickly return to that record at any time after moving to a different record, set the Recordset object's Bookmark property to the value of that variable.
There is no limit to the number of bookmarks you can establish. To create a bookmark for a record other than the current record, move to the desired record and assign the value of the Bookmark property to a String variable that identifies the record.
To make sure the Recordset object supports bookmarks, check the value of its Bookmarkable property before you use the Bookmark property. If the Bookmarkable property is False, the Recordset object doesn't support bookmarks, and using the Bookmark property results in a trappable error.
If you use the Clone method to create a copy of a Recordset object, the Bookmark property settings for the original and the duplicate Recordset objects are identical and can be used interchangeably. However, you can't use bookmarks from different Recordset objects interchangeably, even if they were created by using the same object or the same SQL statement.
If you set the Bookmark property to a value that represents a deleted record, a trappable error occurs.
The value of the Bookmark property isn't the same as a record number.
补充：VB , 数据库(包含打印，安装，报表)
