Title: Cloning a ClientDataset
Question: Cloning ClientDatasets may be usefull when using temporary dataset for simulation purposes.
Answer:
The first procedure clones a clientdataset field defs and the second copies all records from one to another:
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//FromDataset: the source dataset
//ToDataset: the target dataset
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procedure CloneClientDataset(FromClientDataset, ToClientDataset: TCustomClientDataset);
var
i: integer;
begin
ToClientDataset.Close;
ToClientDataset.Fields.Clear;
ToClientDataset.FieldDefs.Clear;
for i:= 0 to FromClientDataset.FieldDefs.Count - 1 do
if FromClientDataset.FieldDefs[i].DataType ftDataSet then
begin
with ToClientDataset.FieldDefs.AddFieldDef do
Assign(FromClientDataset.FieldDefs[i]);
end;
ToClientDataset.CreateDataSet;
end;
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//FromDataset: the source dataset
//ToDataset: the target dataset
//FieldNames: a array os strings representing the names of the fields to have
//their values copied.
------------------------------------
procedure CloneFieldsValues(FromDataset, ToDataset: TClientDataset; FieldNames: array of string);
var
FromField, ToField: TField;
i: integer;
begin
for i:= low(FieldNames) to High(FieldNames) do
begin
FromField:= FromDataset.FindField(FieldNames[i]);
ToField:= ToDataset.FindField(FieldNames[i]);
if assigned(FromField) and assigned(ToField) then
ToField.Value:= FromField.Value;
end;
end;