[MS-EXCEL] excel XLUnicodeRichExtendedString length not equal the sum of the lengths of ites items?

Question

I want to get all the Strings in an excel , I know it stores in the SST , when I analyze the SST use offvis , I find something I cannot understand , some XLUnicodeRichExtendedString size not equal the sum of the length of the items in it , How can I obtain the correct length？

ie, XLUnicodeRichExtendedString[272] size is 34 , WHY? the sum of the length of cch/flags/rgbString is 30 ？

Answer 1

I know the answer by reading the sourcecode of libxls , I cannot parse XLUnicodeRichExtendedString as a list , the XLUnicodeRichExtendedString data is in SST(type = 252) or Continue (type = 60) sector , one XLUnicodeRichExtendedString may cross over a sector

thanks