Display BLOB fields in an inline or HREF linked mode.

dbQP Abbr: bb
Version: All

Namespace:  Tornado
Assembly:  Tornado (in Tornado.dll) Version: 12.6.0.9 (1.0.0.0)

Syntax

C#
public string dbBLOB { get; set; }
Visual Basic (Declaration)
Public Property dbBLOB As String

Field Value

Obj.dbBLOB = "Field| Context| Label | Offset"
KeywordDescription
FieldFieldNameOrNumber is the Database field that is of BLOB type (128, 204, 205).
Context The HTML context type (image/jpg, image/bmp, image/gif, application/msexcel etc.). Use 'Auto' tolet ASP-db auto detect the context type (gif, jpg, png and pdf). These can be found in your browser’s “Helper Apps”).

2005 new implementation - Auto (Autodetect BLOB Type - gif, jpg, png, bmp and pdf only). Default = "text/html" which covers Ascii mode also. You can mix the type of Blobs stored in the field and display in the inline mode. Inline does not need any context. This implementation is truely amazing.

LabelThis text will be displayed when Linked images are used instead of in-line images.
Offset "Browser" = Inline display with no hyperlink. Every database implements BLOBs differently. When binary objects are stored in the data field with an attached header, you must determine how many bytes (if any) are delivered in front of the actual binary data. Some examples are:

* DB2 BLOB field - Offset = 0

* ACCESS OLE-OBJ field containing BMP images – Offset = 78 (NWIND Employee Table example)

* Borland Paradox’s BLOB field storing images (Biolife example) – Offset = 8

Set Offset to –1 if hyperlinking is not desired. In this case, the image will be displayed “in-line”.

Remarks

* dbBookMark = Tablename; key_field MUST be used with dbBLOB in order tolocate the records upon postback.

* Different DB has their BLOB fields defined differently. The fields are sometimes stored with a header. Use must know the format of these BLOBs in order to have them displayed properly.

* For inline display, dbBookMark must be specified. Only the table name of the BookMark is used upon re-entrance image display.

Examples

CopyVB.NET
.dbBlob = "field=Pic|<b>context=auto</b>|label=Hyperlink to Blob|offset=0"
.dbBlob = "field=logo|context=image/gif|label=browser|offset=0"
.dbBlob = "field=Photo|context=Auto|label=browser|offset=0"
CopyVB.NET
<script language="vb" runat="server">
Sub Page_Load(Source as Object, E as EventArgs)
Dim BGif As New Tornado.Z()
  With BGif
    .dbQP = "U=92|S=14|dt=SQL|th=ti=Blob Demo"
    .dbSQL="SELECT pub_id, logo From pub_info"
    .dbDSN="fujitsu;pubs;sa;sa"
    .dbBookMark = "pub_info;0"  '.... Musthave this property    
    .dbBlob = "field=logo|context=image/gif|label=browser|offset=0"
    .ASPdbNet
  End With
End Sub
</script>

See Also