keep Merging Datatable by using for loop

DataTable skillCandidate = new DataTable();
DataTable candidateIds=new DataTable();
DataSet candidateIds = new DataSet();
candidateIds = Grrasp.Business.Candidate.Manager.GetCandidateId(skillId);
DataTable result = new DataTable();
foreach (DataTable dt in candidateIds.Tables)
{
result.Merge(dt);
}
gvCandidateList.DataSource = result;
gvCandidateList.DataBind();