怎么把一個字符串中指定位置變成小寫？

raoweijian

比如一個字符串全是字母，ATATACTCTCGGGACA，類似這樣的，然后指定從比如100-200變成小寫，其他不變，怎么實現(xiàn)？

grshrd49

1. $string = "aaaaaaaaaaaa";
   
2. @fensan = split //,$string;
   
3. $fensan[$_] = uc($fensan[$_]) for(3..6); #這里是下標,記得要+1
   
4. $string = join "",@fensan;
   
5. print $string;

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uc()大寫
lc()小寫

當然也可以用str()字符串處理函數(shù)
樓主搞本小駱駝書 通讀一邊這些簡單的處理都能摸透拉

kk861123

1. substr($str,100,200) = lc(substr($str,100,200));

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rubyish

1. my $s = 'ATATACTCTCGGGACA';
   
2. sub hello {
   
3.     my ( $S, $h, $t ) = @_;
   
4.     my $T = $t - $h + 1;
   
5.     substr $S, $h, $T, lc substr $S, $h, $T;
   
6.     $S;
   
7. }
   
8. my $new = hello $s, 3, 5;
   
9. say $new;

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rubyish

1. ATAtacTCTCGGGACA

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mcshell

1. my $str = "ATATACTCTCGGGACA";
   
2. my ($m,$n) = (3,5);
   
3. my $x = $n-$m+1;
   
4. $str =~ s/^(.{$m})(.{$x})/$1.lc($2)/eg;
   
5. print $str;

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{:3_199:}

grshrd49

回復 6# mcshell


6樓啊，你的簽名的gif圖片晃的我頭暈啊，每次看你的回復只能刪掉你的簽名圖片才能認真看下去....

mcshell

回復 7# grshrd49


    再看一次{:3_186:} {:3_186:}{:3_186:}

grshrd49

回復 8# mcshell


    我  恨   你   

hbmhalley

$_=lc for (substr($YOURSTR, 100, 101)) ;