string xblx = dw1.GetItemString(row, "c_xblx");

string xbid =  dw1.GetItemString(row, "c_xbid");

string express = "evaluate('sum(if(c_xblx=\"" + xblx + "\"" + " and " + "c_xbid=\"" + xbid + "\", d_cfmj, 0) for all)',1)";

string cfmjstr = dw1.Describe(express);

double cfmj = 0;

Double.TryParse(cfmjstr, out cfmj);

evaluate('sum(if(c_xblx="xbm" and c_xbid="14330", d_cfmj, 0) for all)',1)