Displaying blob image extracted from SQLitye DB at TAdvStringGrid

[ninadbe]

I have been making an application at Delphi XE3. I am trying to display values from database to the TAdvStringGrid component placed
on the form. I am using dataset to display results at TAdvSTringGRid (code is given below).
All other values are displaying perfectly except Image in database. Where it is expected to show image, it is showing junk characters.

How to display image perfectly from DataBase at TAdvStringGrid.?

Code: Select all

while not results.EOF do
begin
if (j>sg.rowcount) then
sg.rowcount := sg.rowcount + 1;
for i := 0 to results.fields.Count - 1 do
begin
if i=0 then

else if i = 4 then
//Here I want to display image from db
else
sg.cells[i,j] := results.FieldByName(names[i]).AsString;
end;
results.Next;
inc(j);
end;  

The methods mentioned in manual to display image are as follows

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Grid.CreatePicture(2,3,True,Shrink,0,haLeft,vaTop).LoadFromFile(‘TST.JPG’);
procedure AddPicture(ACol,ARow: Integer;APicture:TPicture;transparent: Boolean; stretchmode:TStretchMode; padding: Integer; hal:TCellHalign; val:TCellValign);
function GetPicture(ACol,ARow: Integer): TPicture;
Grid.CreateFilePicture(2,3,True,Shrink,0,haLeft,vaTop).Filename := ‘TST.JPG’;  

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function CreatePicture(ACol,ARow:Integer; transparent:Boolean; stretchmode:TStretchMode; padding:Integer; hal:TCellHalign; val:TCellValign):TPicture; 


function AddPicture(ACol,ARow:Integer; aPicture:TPicture; transparent:Boolean; stretchmode:TStretchMode; padding:Integer; hal:TCellHalign; val:TCellValign):TPicture; 

But it is not given there how to display it with dataset.

When used with static image from file the code works well problem only with TStram & TPicture while working with DataSet. DataSet is extracting image in junk characters format as it is BLOB type.

This works well

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            try
               Picture.LoadFromFile('C:\dattaguru.png');
               sg.AddPicture(i,j,Picture,True,ShrinkWithAspectRatio,0,haLeft,vaTop);
           finally
               Stream1.Free;

While this dont work , gives SQLException error.

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            try
               Field := TBlobField(results.FieldByName(names[i]).AsString);
               Stream := results.CreateBlobStream(Field, bmReadWrite);
               Picture.Graphic.LoadFromStream(Stream1);
               sg.AddPicture(i,j,Picture,True,ShrinkWithAspectRatio,0,haLeft,vaTop);
           finally
               Stream1.Free;

Anypone has idea how to LoadFromStream data at TPicture ? or how it can be done?

[AlexP]

Hello,

To load data from a BLOB field to Stream, you needn't to map the field to string, You can directly save data to Stream in the following way:

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TBlobField(results.FieldByName(names[i]).SaveToStream(Stream1);