python字符串第一个字符怎么表示 JavaScript中如何截取字符串的第一个字符？
python\u600e\u4e48\u628a\u5b57\u7b26\u4e32\u7b2c\u4e00\u4e2a\u5b57\u7b26\u53bb\u63891\u3001\u65b0\u5efa\u4e00\u4e2aphp\u6587\u4ef6\uff0c\u547d\u540d\u4e3atest.php\uff0c\u7528\u4e8e\u8bb2\u89e3php\u5982\u4f55\u5220\u9664\u5b57\u7b26\u4e32\u7b2c\u4e00\u4e2a\u5b57\u7b26\u3002
2\u3001\u5728test.php\u6587\u4ef6\u4e2d\uff0c\u4f7f\u7528header()\u65b9\u6cd5\u5c06\u9875\u9762\u7684\u7f16\u7801\u683c\u5f0f\u8bbe\u7f6e\u4e3autf-8\uff0c\u907f\u514d\u8f93\u51fa\u4e2d\u6587\u4e71\u7801\u3002
3\u3001\u5728test.php\u6587\u4ef6\u4e2d\uff0c\u5c06\u8981\u5220\u9664\u7684\u5b57\u7b26\u4e32\u5b58\u653e\u5728$str\u53d8\u91cf\u4e2d\u3002
4\u3001\u5728test.php\u6587\u4ef6\u4e2d\uff0c\u4f7f\u7528substr()\u51fd\u6570\u4ece\u5b57\u7b26\u4e32\u7b2c\u4e8c\u4e2a\u5b57\u7b26\u5f00\u59cb\u622a\u53d6\u81f3\u672b\u5c3e\u5b57\u7b26\u4e32\uff0c\u540c\u65f6\u5c06\u622a\u53d6\u540e\u7684\u5b57\u7b26\u4e32\u66ff\u6362\u539f\u5b57\u7b26\u4e32$str\u3002
5\u3001\u5728test.php\u6587\u4ef6\u4e2d\uff0c\u4f7f\u7528echo\u8f93\u51fa\u622a\u53d6\u540e\u7684\u7ed3\u679c\u3002
6\u3001\u5728\u6d4f\u89c8\u5668\u6253\u5f00test.php\u6587\u4ef6\uff0c\u67e5\u770b\u7ed3\u679c\u3002
var str="Hello world!";
document.write(str.charAt(0)); //charAt()\u65b9\u6cd5\u53ef\u8fd4\u56de\u6307\u5b9a\u4f4d\u7f6e\u7684\u5b57\u7b26\u3002
//JavaScript \u5e76\u6ca1\u6709\u4e00\u79cd\u6709\u522b\u4e8e
// \u5b57\u7b26\u4e32\u7c7b\u578b\u7684\u5b57\u7b26\u6570\u636e\u7c7b\u578b\uff0c
// \u6240\u4ee5\u8fd4\u56de\u7684\u5b57\u7b26\u662f\u957f\u5ea6\u4e3a 1 \u7684\u5b57\u7b26\u4e32
\u4ee5\u4e0a\u4ee3\u7801\u7684\u8f93\u51fa\u662f\uff1a
H \u5373\u7b2c\u4e00\u4e2a\u5b57\u7b26
print(s[0])
绛旓細return s[0:len(s)] + letter # 浣跨敤瀛楃涓插垏鐗囧姛鑳戒粠绗竴涓瀛楁瘝寮濮嬶紝鐩村埌杈撳叆鐨勫瓧姣嶄负姝 s = "Hello, world!"letter = "o"result = write_letters(s, letter)print(result) # 杈撳嚭锛歟llo, world!o 鍦ㄤ笂闈㈢殑绀轰緥涓紝鎴戜滑瀹氫箟浜涓涓瓧绗︿覆`s`鍜屼竴涓瓧姣峘letter`锛岀劧鍚庤皟鐢╜write_letters`...
绛旓細鍦ㄥぇ澶氭暟缂栫▼璇█閲岄潰锛屼笅鏍囬兘鏄粠0寮濮嬬殑锛Python涔熶笉渚嬪銆傜0涓厓绱犲氨鏄寚鏈宸﹁竟鐨勫厓绱犮備笉绠¤繖涓瀛楃涓鏈夊闀匡紝Python璇█璁＄畻涓涓瓧绗︿覆闀垮害鐨勬椂鍊欙紝绗竴涓瓧绗浠0寮濮嬨傝繖涓拰鎴戜滑骞虫椂鐨勪範鎯笉澶竴鏍枫傛垜浠钩鏃舵暟涓涓槦鍒楋紝绗竴涓氨鏄暟涓锛屼絾鏄繖閲岀殑绗竴涓氨鏄0銆
绛旓細s="瀛楃涓茬涓涓瓧绗︽庝箞琛ㄧず"print(s[0])
绛旓細绛旀锛s = "Hello Python!"锛宻[3: 8] = "lo Py"瑙锛歴[3: 8] 琛ㄧず鐨勬槸鍒囩墖鎿嶄綔锛屾剰鎬濇槸鍙栬捣濮嬬储寮曪紙鍖呭惈璇ョ储寮曞搴斿硷級3锛岀粓姝㈢储寮曪紙涓嶅寘鍚绱㈠紩瀵瑰簲鍊硷級8 涔嬮棿鐨勫笺傜敱浜庡瓧绗︿覆 s 鐨勭涓涓瓧绗 H 鐨勭储寮曞兼槸 0锛屽洜姝ょ储寮曞 3 鐨勫瓧绗︽槸 l銆傚張鍥犵┖鏍间篃绠椾竴涓瓧绗︼紝鍥犳绱㈠紩鍊 8 ...
绛旓細棰樹富浣犲ソ,浠ｇ爜濡備笅:娴嬭瘯鎴浘濡備笅:--- 甯屾湜鍙互甯埌棰樹富, 娆㈣繋杩介棶.
绛旓細23涓渶甯歌鐨Python瀛楃涓鏂规硶锛1.text.capitalize()锛氬皢瀛楃涓茬殑棣栧瓧姣嶅ぇ鍐 杩欎釜鏂规硶灏嗗瓧绗︿覆鐨绗竴涓瀛楁瘝澶у啓銆傛敞鎰忥紝濡傛灉杩欎釜瀛楃涓叉槸涓涓畬鏁寸殑鍙ュ瓙锛屽畠涓嶄細灏嗘瘡涓崟璇嶉兘澶у啓锛屽彧鏄涓涓瘝銆備緥瀛愶細text='hello'text.capitalize()缁撴灉锛'Hello'2.text.title()锛氬皢瀛楃涓茶浆鎹负鏍囬澶у皬鍐 杩欐槸涓...
绛旓細= "Hello Python!"str1_padded = str1.ljust(50, ' ')print(str1_padded)杩欓噷锛屾垜浠鍏堝畾涔変簡涓涓鍚嶄负str1鐨瀛楃涓锛屽叾鍐呭涓"Hello Python!"銆傜劧鍚庯紝鎴戜滑浣跨敤瀛楃涓茬殑ljust()鏂规硶瀵瑰叾杩涜宸﹀榻愶紝鍚屾椂浣跨敤绌烘牸灏嗗叾闀垮害鎵╁睍鍒50涓瓧绗銆傛渶鍚庯紝鎴戜滑浣跨敤print()鍑芥暟杈撳嚭濉厖鍚庣殑瀛楃涓层
绛旓細琛ㄧず浠绗竴涓瓧绗寮濮嬫埅鍙栵紝闂撮殧2涓瓧绗﹀彇涓涓傝緭鍑虹粨鏋滐細Hlo olH Python 瀵瀛楃涓鍒囩墖 瀵瑰瓧绗︿覆鍒囩墖 瀛楃涓 'xxx'鍜 Unicode瀛楃涓 u'xxx'涔熷彲浠ョ湅鎴愭槸涓绉峫ist锛屾瘡涓厓绱犲氨鏄竴涓瓧绗︺傚洜姝わ紝瀛楃涓蹭篃鍙互鐢ㄥ垏鐗囨搷浣滐紝鍙槸鎿嶄綔缁撴灉浠嶆槸瀛楃涓诧細>>> 'ABCDEFG'[:3]'ABC'>>> 'ABCDEFG'[-3:...
绛旓細鐢╯plit杩欎釜鍑芥暟灏辫锛屽緢绠鍗曠殑 >>> s = "qaz>123>wsx">>> s.split('>')['qaz', '123', 'wsx']>>>
绛旓細1銆佸亣璁鹃渶瑕佸尮閰嶇殑瀛楃涓涓猴細site sea sue sweet see case sse ssee loses 闇瑕佸尮閰嶇殑涓轰互s寮澶翠互e 缁撳熬鐨勫崟璇嶃 姝ｇ‘鐨勬鍒欏紡涓猴細\bs\S*?e\b 2銆佷娇鐢python涓re.findall鍑芥暟琛ㄧず鍖归厤瀛楃涓蹭腑鎵鏈夌殑鍙兘閫夐」锛宺e鏄痯ython閲岀殑姝ｅ垯琛ㄨ揪寮忔ā鍧椼俧indall鏄叾涓涓涓鏂规硶锛岀敤鏉ユ寜鐓ф彁渚涚殑姝ｅ垯琛ㄨ揪寮忥紝鍘...
