I am trying to write a simple string manipulation on a formula field. 

Left (string, N) returns junk character but if I hard code N to some numbers it returns proper string like Left(string, 10) returns good;

Left (string, 10) --> returns good string

Left (string, Instr(string, ">")); --> returns junk

X := InStr(string, ">"); Left (string, X); --> returns junk

Here is my formula field:

local StringVar temp;
local StringVar temp1;
local NumberVar x;
temp := "<span style='font-size:10pt;font-weight:bold;color:red;'>testing</span>";
x := InStr (temp, ">");
temp := Left (temp, x);
if (1=1) then
    temp;

Same case with Left or Right or Mid

Using Visual Studio 2005; CrystalReports.NET