Field Object Record Object COLLECTION: Record::Fields Collection Implemented in version 2.5 The Fields Collection is a collection of all of the Field objects associated with a specific Record object. The Fields Collection has a wider selection of methods than the various other collections in ADO. For example, the Append method allows you to add Field objects to the collection and the Update and CancelUpdate methods give you control over updates. If you reference by name a Field object that does not exist, a new Field object with that name will be appended automatically to the Fields Collection. The Status property for this newly appended Field will be assigned a FieldStatusEnum value of adFieldPendingInsert. Further, if allowed by your provider, the Field will be created in the data source the next time you call the Update method. There are two special fields which can be referenced in a Record object by using the FieldEnum constants. FieldEnum Constants Constant Value Description adDefaultStream -1 References the field containing the default stream adRecordURL -2 References the field containing the absolute URL A Recordset object can also have a Fields Collection. The Fields Collection has two properties and six methods.   PROPERTIES   Count Property The Count property returns a long value that is the number of items in the collection. The counting starts at zero. You can use this value to loop throught the collection by iterating from zero to the value of Count minus one.   Code (VBScript): intCountNumber = objRecord.Fields.Count   You can also use the VB/VBScript For Each ... Next statement.   Code (VBScript): For Each objField In objRecord.Fields    ' place code here to manipulate each item in collection Next   Item Property The Item property is used to return a specific member of the fields Collection. The Index parameter is a variant. It can be the named item or the position (ordinal) number.   Code (VBScript): MyProperty = objRecord.Fields.Item(5) Or: MyProperty = objRecord.Fields(5) Or: MyProperty = objRecord.Fields("Transaction DDL")   METHODS   Append Method The Append method is used to add (append) a Field object to the Fields Collection. Using this method, you can both append and assign a value to the object at the same time. This is useful, because the Value property must first be set and an Update must have occured, before you can set any other properties. There are three data types for the Field object that cannot be appended to the Fields Collection. If you try to use adArray, adChapter, or adEmpty, an error will occur. syntax: Fields.Append Name, Type, DefineSize, Attrib, FieldValue This method has five optional parameters. The optional Name is the unique name of the new Field object being appended to the collection. The optional Type is one of the DataTypeEnum constants that defines the data type of the new Field.   DataTypeEnum Constants   Constant Value Description adArray 0x2000 Combine with another data type to indicate that the other data type is an array adBigInt 20 8-byte signed integer adBinary 128 Binary adBoolean 11 True or false Boolean adBSTR 8 Null-terminated character string adChapter 136 4-byte chapter value for a child recordset adChar 129 String adCurrency 6 Currency format adDate 7 Number of days since 12/30/1899 adDBDate 133 YYYYMMDD date format adDBTime 134 HHMMSS time format adDBTimeStamp 135 YYYYMMDDHHMMSS date/time format adDecimal 14 Number with fixed precision and scale adDouble 5 Double precision floating-point adEmpty 0 no value adError 10 32-bit error code adFileTime 64 Number of 100-nanosecond intervals since 1/1/1601 adGUID 72 Globally unique identifier adIDispatch 9 Currently not supported by ADO adInteger 3 4-byte signed integer adIUnknown 13 Currently not supported by ADO adLongVarBinary 205 Long binary value adLongVarChar 201 Long string value adLongVarWChar 203 Long Null-terminates string value adNumeric 131 Number with fixed precision and scale adPropVariant 138 PROPVARIANT automation adSingle 4 Single-precision floating-point value adSmallInt 2 2-byte signed integer adTinyInt 16 1-byte signed integer adUnsignedBigInt 21 8-byte unsigned integer adUnsignedInt 19 4-byte unsigned integer adUnsignedSmallInt 18 2-byte unsigned integer adUnsignedTinyInt 17 1-byte unsigned integer adUserDefined 132 User-defined variable adVarBinary 204 Binary value adVarChar 200 String adVariant 12 Automation variant adVarNumeric 139 Variable width exact numeric with signed scale adVarWChar 202 Null-terminated Unicode character string adWChar 130 Null-terminated Unicode character string   The optional DefinedSize parameter is a long value that is the size in bytes or characters of the new Field. When DefinedSize exceeds 255 bytes, the field is treated as having variable length columns. The optional Attrib parameter is one of the FieldAttributeEnum constants that specify the attributes of the new Field. FieldAttributeEnum Constants   Constant Value Description adFldCacheDeferred 0x1000 Provider caches values and reads from cache adFldFixed 0x10 Fixed-length data adFldIsChapter 0x2000 Chapter value with specified child recordset adFldIsCollection 0x40000 Collection of resources adFldIsDefaultStream 0x20000 Contains default stream adFldIsNullable 0x20 Accepts null values adFldIsRowURL 0x10000 Contains URL to resource in data source adFldKeyColumn 0x8000 Primary key or part of primary key adFldLong 0x80 Long binary field and can use AppendChunk and GetChunk methods adFldMayBeNull 0x40 Can read null values adFldMayDefer 0x2 Values are not retrieved with whole record adFldNegativeScale 0x4000 Can support negative scale values adFldRowID 0x100 Contains a row identifier used only to ID the row adFldRowVersion 0x200 Uses time/date to track updates adFldUnknownUpdatable 0x8 Provider cannot determine if you can write to field adFldUnspecified -1 Does not specify attributes adFldUpdatable 0x4 Can write to field   The optional FieldValue parameter is a variant that is the value for the new Field. If this parameter is not provided, it will be set to null when the new Field is appended. Code (VBScript): objRecord.Fields.Append "Age", adInteger   CancelUpdate Method  Implemented in version 2.5 The CancelUpdate method cancels all pending deletions, insertions, or updates to the Fields Collection for a specific Record object. All existing Field objects are returned to the value they had after the last call of the Update method (if a call occurred). The status value is set to adFieldOK for all Field objects in the collection. This method has no parameters. Code (VBScript): objRecord.Fields.CancelUpdate Delete Method The Delete method designates that a specified Field object is to be deleted from the Fields Collection. You must call the Update method of the Fields Collection to make this deletion.   Syntax: Fields.Delete Index This method has one parameter. The Index parameter is either the name property or the ordinal position (index) in the collection of the Field object. Code (VBScript): objRecord.Fields.Delete 3   Refresh Method Although, the Refresh method is used to update objects in a collection, this method has no effect on the Fields Collection of the Record object. Resync Method  Implemented in version 2.5 The Resync method is used to refetch the data from the underlying data source and to update (resynchronize) the values in the OriginalValue, UnderlyingValue, and Value properties of Field objects that are in the Fields Collection object of a Record object, or just to update the UnderlyingValue property. The effect of calling this method will depend on the value of the Status for each Field object. For example, Field objects with an adFieldPendingUnknown or adFieldPendingInsert status are not affected by calling this method. This method has one optional parameter. The optional ResyncValues parameter is one of the ResyncEnum constants that determines which values can be overwritten. The default is to update the OriginalValue, UnderlyingValue, and Value properties.   ResyncEnum Constants Constant Value Description adResyncAllValues 2 Default, can overwrite all values, and pending updates are cancelled adResyncUnderlyingValues 1 Can only overwrite underlying values, and pending updates are not cancelled Code (VBScript): objRecord.Fields.Resync adResyncUnderlyingValues   Update Method  Implemented in version 2.5 The Update method is called to make additions, deletions, and updates to the Fields Collection of the Record object. Code (VBScript): objRecord.Fields.Update   Copyright 1999-2001 by Infinite Software Solutions, Inc. All rights reserved. Trademark Information