Length of string in Perl independent of character encoding -

-

the length function assumes chinese characters more 1 character. how determine length of string in perl independent of character encoding (treat chinese characters 1 character)?

the length function operates on characters, not octets (aka bytes). definition of character depends on encoding. chinese characters still single characters (if encoding correctly set!) take more 1 octet of space. so, length of string in perl dependent on character encoding perl thinks string in; string length independent of character encoding simple byte length.

make sure string in question flagged utf-8 , encoded in utf-8. example, yields 3:

$ perl -e 'print length("长")'

whereas yields 1:

$ perl -e 'use utf8; print length("长")'

as does:

$ perl -e 'use encode; print length(encode::decode("utf-8", "长"))'

if you're getting chinese characters file, make sure binmode $fh, ':utf8' file before reading or writing it; if you're getting data database, make sure database returning strings in utf-8 format (or use encode you).

i don't think have have in utf-8, need ensure string flagged having correct encoding. i'd go utf-8 front (and sideways) though that's lingua franca unicode , make things easier if use everywhere.

you might want spend time reading perlunicode man page if you're going dealing non-ascii data.


Comments

Post a Comment

Popular posts from this blog

c# - How to set Z index when using WPF DrawingContext? -

-
how set z-index drawing object when using drawingcontext.drawxxx() methods? the object drawn last have higher z index. can't change index of drawn objects. way draw in order. if using wpf (as placed tag), can use, example, canvas control. create shapes need like polyline obj = new polyline(); //... // ... set properties of obj and add them canvas uielementcollection: yourcanvasname.children.add(obj); //or yourcanvasname.children.insert(i, obj); first items of collection have higher z index. advantages in way: no need redraw on window changes, can anytime move objects , change order.
Read more

razor - Is this a bug in WebMatrix PageData? -

-
i think may have found bug in webmatrix's pagedata, not sure. concerns how pass data partial page calling page. in webmatrix documentation (tutorials, e.g. " 3 - creating consistent look ", , example code), pagedata recommended mechanism pass data between pages (e.g. content page layout page, or partial page). however have found not work other way, pass data partial page calling page. modifying or adding entries in pagedata in partial page, not seem calling page. cutting right down simplest possible example, in test page may have this: @{ pagedata["test"] = "initial entry"; } <p>before calling partial page, test value @pagedata["test"]</p> @renderpage("_testpartial.cshtml") <p>after returning calling page, test value @pagedata["test"]</p> and in _testpartial.cshtml page might have this: @{ pagedata["test"] = "modified entry"; } <p>in partial page...
Read more

visual c++ - Using relative values in array sorting ( asm ) -

-
i need sort through array , sort each individual row in array in ascending order. doesn't seem going (surprise!) keep getting hit 2 errors: a2101: cannot add 2 relocatable labels , a2026: constant expected here's sort, makes sense me, think i'm still trying implement high-lvl language techniqes assembly. there way around not being able use relative values? (the array 7 rows 9 columns, btw). mov cx, 7; cx = number of rows outer: ; outer loop walk through rows push cx mov cx, 9 mov row, cx ;rows middle: ; middle-loop walk through columns push cx sub cx, 1 ;cx = cx-1 mov column, cx ;columns inner: ;inner loop - compare , exchange column values cmp marray[row*9 + column], marray[row*9 + column+1] xchg marray[row*9 + column+1], marray[row*9 + column] ; compare , exchange values marray table inc column loop inner pop cx loop mid...
Read more