TClientDataSet faulted with message

1
votes

got a small situation here, I haven't used TClientDataSet until recently(it requires midas.dll) so now I'm facing a very awkward error, not very descriptive:

Debugger Fault Notification

Project E:\Work\XXX\binary\XXX.exe faulted with message: 'access violation at 0x00678827: write of address 0x00030a38'. Process Stopped. Use Step or Run to continue.

this happens whenever I try to set the value of a field in the clientdataset(I'm using it as a in-memory dataset) as so:

with ADataModule do begin
  cdsTest.Append;
  cdsTestAField.AsString := ATableField.AsString;
  // ...
end;

both fields are TStringField, cdsTestAField has size 64 and ATableField has size 32

Note: that I'm calling the CreateDataSet method before anything else, also this happens only with the string fields, any help would be highly appreciated.

Thank you for your time.

1
delphitclientdataset
Be careful using with; when ADataModule does not include cdsTest, but your current scope does, then you can get yourself in deep trouble. - Jeroen Wiert Pluimers
thank you for the heads up Jeroen, but I always keep non-visual components on the datamodule. - user497849

1 Answers

3
votes

And where does ATableField come from? Could it be that it is an invalid reference to an object that is already freed?

Also, you can include midaslib.pas in your project to eliminate the use of an external midaslib.dll. It will make your project slightly larger, though, because you are basically compiling the dll in you exe.