Changes

String Functions and Manipulation in VB6

831 bytes added, 21:14, 15 February 2008
/* Null, 0, and Empty Strings */
The following lines were added (+) and removed (-):
In VB, Null is a subtype of a Variant, in the same way the Empty is also. In other words, Null and Empty are both special states of a Variant variable.vbNull and vbEmpty are the codes returned from the VarType function when applied to a value of that type, e.g.    VarType(Empty) = vbEmpty    VarType(Null) = vbNullThis provides one method of testing whether a value is Null or Empty. The other is by calling the IsNull and IsEmpty functions.In a database, NULL has a similar status to Null is VB Variants, althoughit's defined by the SQL standard rather than the VB language.Use the NULL keyword to assign Null to a recordset field, use the IsNull function to test if a recordset fields contains Null.Null: Used for writing NULL in SQL standard, a NULL to the database, which will appear as a 0 in a numeric field.
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