Answer:
// C# convert a byte array to a string. object data= httpanalyzer.Log[0].Content.Data;
byte[] bytes= (byte[])data;
string str = System.Text.Encoding.Default.GetString(bytes);
//delphi convert a byte array to a string functionConvertByteArrayToString(const V:OleVariant):string;
var
count: Integer;
ptr: Pointer;
begin
Result:='';
if VarIsNull(V) then
Exit;