Find all close price between two dates

Hello,
I want to find all closing price between two dates e.g. 2016-01-26 and
2016-02-26

My thought is to use for loop

D[1] = "2016-07-26";
D[2]= "2016-07-27";
D[3]= "2016-07-28";
.
.
.

for (i=1;i<3;i++) {

"Close value at (or before) " + D+ " is " + Lookup( Close, _DT(D ), -1 );
}

But it seem not work, any help for advanced thanks

Using the for loop, actually i want to find the highest and lowest close price between two dates
e.g. 2012-05-12 and 2016-05-12
i consider to use datenum(), but still no result

tn = DateNum();
startDate =5750521;
endDate =5800512;
StartBar = tn == startDate;
EndBar = tn == endDate;
dn = DateNum();
marray = IIf(tn >= startDate AND tn <= endDate, Close, Null);
hv = Highest(m1array);
lv = Lowest(mrray);
Plot( hv, "myH", colorGreen, styleThick );
Plot( lv, "myL", colorRed, styleThick );