{"id":12210,"date":"2021-01-15T00:00:00","date_gmt":"2021-01-14T16:00:00","guid":{"rendered":"https:\/\/fgchen.com\/wpedu2\/2021\/01\/15\/javascript%e5%bf%ab%e9%80%9f%e5%85%a5%e9%96%80-%e5%ad%97%e4%b8%b2%e3%80%81%e9%99%a3%e5%88%97%e8%88%87%e7%89%a9%e4%bb%b6\/"},"modified":"2026-03-30T14:39:29","modified_gmt":"2026-03-30T06:39:29","slug":"javascript%e5%bf%ab%e9%80%9f%e5%85%a5%e9%96%80-%e5%ad%97%e4%b8%b2%e3%80%81%e9%99%a3%e5%88%97%e8%88%87%e7%89%a9%e4%bb%b6","status":"publish","type":"post","link":"https:\/\/fgchen.com\/wpedu\/2021\/01\/javascript%e5%bf%ab%e9%80%9f%e5%85%a5%e9%96%80-%e5%ad%97%e4%b8%b2%e3%80%81%e9%99%a3%e5%88%97%e8%88%87%e7%89%a9%e4%bb%b6\/","title":{"rendered":"JavaScript\u5feb\u901f\u5165\u9580 – \u5b57\u4e32\u3001\u9663\u5217\u8207\u7269\u4ef6"},"content":{"rendered":"

Strings\u00a0<\/b><\/h1>\n\n
let str = 'Hi';\nlet greeting = \"Hello\";\n<\/pre>\n\n \n\n
\u8df3\u812b\u5b57\u5143 Escape Characters<\/b><\/h2>\n\n\u8df3\u96e2\u672c\u8eab\u5b57\u5143\u6240\u4ee3\u8868\u7684\u610f\u7fa9\uff0c\u5728\u4e00\u500b\u5b57\u4e32\u8868\u793a\u4e2d\uff0c\u82e5\u8981\u8f38\u51fa”\uff0c\u8981\u5beb\u6210\uff1a”””\uff0c\u5426\u5247\u7b2c2\u500b”\u6703\u88ab\u7576\u6210\u5b57\u4e32\u5b57\u5143\uff0c\u7b2c3\u500b\u5b57\u4e32\u5b57\u5143”\u88ab\u7576\u6210\u591a\u9918\u7684\u5b57\u4e32\u5b57\u5143\u3002\n\n‘ \u2014 Single quote\u00a0<\/b>\n\n” \u2014 Double quote\u00a0<\/b>\n\n \u2014 Backslash\u00a0<\/b>\n\nb \u2014 Backspace \u5230\u9000<\/b>\n\nf \u2014 Form feed\uff0c\u63db\u9801\uff0c\u9032\u7d19<\/b>\n\nn \u2014 New line \uff0c\u65b0\u884c<\/b>\n\nr \u2014 Carriage return \uff0c\u6e38\u6a19\u56de\u5230\u4e00\u958b\u59cb\u7684\u4f4d\u7f6e<\/b>\n\nt \u2014 Horizontal tabulator\uff0c\u6c34\u5e73\u5b9a\u4f4d<\/b>\n\nv \u2014 Vertical tabulator \uff0c\u5782\u76f4\u5b9a\u4f4d<\/b>\n\n \n\n
Windows line break: 'rn'\nUnix line break: 'n'\nTab: 't'\nBackslash ''<\/pre>\n\n
<\/h2>\n\n
String \u65b9\u6cd5<\/b><\/h2>\n\ncharAt()\u00a0<\/b>\n\n\u56de\u50b3\u5b57\u4e32\u4e2d\u7684\u7279\u5b9a\u4f4d\u7f6e\u8655\u7684\u5b57\u5143 (\u5c07\u5b57\u4e32\u8996\u70ba\u5b57\u5143\u7684\u9663\u5217\uff0c\u7d22\u5f15\u503c\u5f9e0\u958b\u59cb)<\/span>\n\n
var str = 'hello world';\n\n\/\/ \u8f38\u51fa 'e'\nconsole.log(str.charAt(1));\n\/\/ \u8f38\u51fa 'h'\nconsole.log(str.charAt(0));<\/pre>\n\ncharCodeAt()\u00a0<\/b>\n\n\u53d6\u5f97<\/span>\u5b57\u4e32\u7279\u5b9a\u4f4d\u7f6e\u7684\u5b57\u5143\u7684 Unicode \u7de8\u78bc<\/span>\n\n
var str = 'hello world';\n\n\/\/ \u8f38\u51fa 104\nconsole.log(str.charCodeAt(0));\n\/\/ \u8f38\u51fa 101\nconsole.log(str.charCodeAt(1));<\/pre>\n\nconcat()\u00a0<\/b>\n\n\u5e7e\u500b<\/span>\u5b57\u4e32\u76f8\u52a0\uff0c\u7136\u5f8c\u8fd4\u56de\u4e00\u500b\u65b0\u5b57\u4e32<\/span>\n\n
var hello = 'Hello, ';\n\/\/ \u8f38\u51fa 'Hello, Mike have a nice day.'\nconsole.log(hello.concat('Mike', ' have a nice day.'));<\/pre>\n\n\u7c21\u55ae\u4e00\u9ede\uff0c\u4f7f\u7528+\u5c31\u53ef\u4ee5\u9023\u63a52\u500b\u5b57\u4e32\uff1a\n\n
var hello = 'Hello, ';\n\/\/ \u8f38\u51fa 'Hello, Mike have a nice day.'\nconsole.log(hello + 'Mike' + ' have a nice day.');<\/pre>\n\nfromCharCode()\u00a0<\/b>\n\n\u56de\u50b31\u6216\u591a\u500b\u6307\u5b9a\u7684unicode\u7de8\u78bc\u7684\u5b57\u7b26(\u4e32)<\/span>\n\n
String.fromCharCode(72,69,76,76,79);\n\/\/HELLO\n\nString.fromCharCode(65,66,67);\n\/\/ABC<\/pre>\n\nindexOf()\u00a0<\/b>\n\n\u5224\u65b7\u5b57\u4e32<\/span>\u5b57\u4e32\u8b8a\u6578\u4e2d\u662f\u5426\u5305\u542b\u67d0\u5b57\u4e32\uff0c<\/span>\u8fd4\u56de\u627e\u5230\u7684\u4f4d\u7f6e\uff0c\u7b2c\u4e00\u500b\u4f4d\u7f6e\u5f9e 0 \u958b\u59cb\u7b97\u8d77\uff1b\u627e\u4e0d\u5230\u5247\u8fd4\u56de -1\n\n
'Blue Whale'.indexOf('Blue');         \/\/ 0\n'Blue Whale'.indexOf('Blute');        \/\/ -1\n'Blue Whale'.indexOf('Whale', 0);     \/\/ 5\n'Blue Whale Blue'.indexOf('Blue', 5); \/\/ 11<\/pre>\n\nlastIndexOf()\u00a0<\/b>\n\n\u627e\u51fa\u4e00\u500b<\/span>\u5b57\u4e32\u5728\u53e6\u4e00\u500b\u5b57\u4e32\u4e2d\u6700\u5f8c\u51fa\u73fe\u7684\u4f4d\u7f6e\u3002<\/span>\n\n
var str = 'Brave new world';\n\nstr.lastIndexOf('w'); \/\/ 10\nstr.lastIndexOf('g'); \/\/ -1<\/pre>\n\nmatch()\u00a0<\/b>\n\n\u642d\u914d<\/span>\u6b63\u898f\u8868\u793a\u5f0f<\/a> (<\/a>Regex)<\/a>\u4f86\u627e\u51fa<\/span>\u5b57\u4e32\u4e2d\u5339\u914d\u7684\u5167\u5bb9\u3002<\/span>\n\n\u8fd4\u56de\u4e00\u500b<\/span>\u9663\u5217\uff0c\u7b2c\u4e00\u500b\u5143\u7d20\u662f\u5b8c\u6574\u5339\u914d\u5167\u5bb9\uff0c\u63a5\u8457\u662f\u5339\u914d\u7684\u7fa4\u7d44 (capturing group)\uff1b\u5982\u679c\u6c92\u6709\u5339\u914d\u5247\u8fd4\u56de null\u3002<\/span>\n\n
var str = 'For more information, see Chapter 3.4.5.1';\nvar re = \/see (chapter d+(.d)*)\/i;\nvar found = str.match(re);\n\n\/\/ \u8f38\u51fa [\"see Chapter 3.4.5.1\", \"Chapter 3.4.5.1\", \".1\"]\nconsole.log(found);<\/pre>\n\nreplace()\u00a0<\/b>\n\n\u5b57\u4e32\u53d6\u4ee3\n\nsearch()\u00a0<\/b>\n\n\u627e\u51fa\u4e00\u500b<\/span>\u5b57\u4e32<\/a>\u5728\u53e6\u4e00\u500b\u5b57\u4e32\u4e2d\u7684\u4f4d\u7f6e\u3002search() \u7684\u7528\u9014\u8ddf\u00a0<\/span>indexOf()<\/a>\u00a0\u76f8\u4f3c\uff0c\u53ea\u662f search() \u53ef\u4ee5\u7528<\/span>\u6b63\u898f\u8868\u793a\u5f0f<\/a>\u7576\u53c3\u6578\u3002\n<\/span>\n\n
var str = 'Apples are red, and apples are good.';\n\/\/ \u8f38\u51fa 0\nconsole.log(str.search(\/apple\/i));<\/pre>\n\nslice()\u00a0<\/b>\n\n\u7528\u4f86\u64f7\u53d6\u4e00\u500b<\/span>\u5b57\u4e32<\/a>\u7684\u5176\u4e2d\u4e00\u90e8\u5206\u3002<\/span>\n\n
var str = 'The morning is upon us.';\n\/\/ \u8f38\u51fa 'he morn'\nconsole.log(str.slice(1, 8));\n\/\/ \u8f38\u51fa 'morning is upon u'\nconsole.log(str.slice(4, -2));\n\/\/ \u8f38\u51fa 'is upon us.'\nconsole.log(str.slice(12));\n\/\/ \u8f38\u51fa\u7a7a\u5b57\u4e32 ''\nconsole.log(str.slice(30));\n\/\/ \u8f38\u51fa 'us.'\nconsole.log(str.slice(-3));\n\/\/ \u8f38\u51fa 'us'\nconsole.log(str.slice(-3, -1));\n\/\/ \u8f38\u51fa 'The morning is upon us'\nconsole.log(str.slice(0, -1));<\/pre>\n\nsplit()\u00a0<\/b>\n\n\u7528\u4f86\u6839\u64da\u4f60\u6307\u5b9a\u7684\u5206\u9694\u7b26\u865f\uff0c\u5c07<\/span>\u5b57\u4e32<\/a>\u5207\u5272\u6210\u4e00\u500b\u5b57\u4e32\u9663\u5217\u3002<\/span>\n\n
var str = 'a,b,c,d,e';\n\nvar strAry = str.split(',');\n\/\/ \u8f38\u51fa [\"a\", \"b\", \"c\", \"d\", \"e\"]\nconsole.log(strAry);\n\n\/\/ \u8f38\u51fa [\"a\", \"b\"]\nconsole.log(str.split(',', 2));<\/pre>\n\n\u5206\u9694\u7b26\u865f\u4e5f\u53ef\u4ee5\u662f\u4e00\u500b<\/span>\u6b63\u898f\u8868\u793a\u5f0f<\/a>\uff1a<\/span>\n\n
var names = 'Harry Trump ;Fred Barney; Helen Rigby ; Bill Abel ;Chris Hand ';\nvar re = \/s*;s*\/;\nvar nameList = names.split(re);\n\/\/ \u8f38\u51fa [\"Harry Trump\", \"Fred Barney\", \"Helen Rigby\", \"Bill Abel\", \"Chris Hand \"]\nconsole.log(nameList);<\/pre>\n\nsubstr()\u00a0<\/b>\n\n\u8ddf\u00a0<\/span>substring()<\/a>,\u00a0<\/span>slice()<\/a>\u00a0\u76f8\u4f3c\u7528\u4f86\u5207\u5272\u5b57\u4e32\uff0c\u53ef\u4ee5\u5f9e\u4e00\u6bb5\u5b57\u4e32\u4e2d\u64f7\u53d6\u5176\u4e2d\u7684\u4e00\u6bb5\uff0c\u5dee\u7570\u5728\u65bc substr() \u7b2c\u4e8c\u500b\u53c3\u6578\u662f\u6307\u5b9a\u8981\u64f7\u53d6\u591a\u9577\u3002<\/span>\n\n\u8a9e\u6cd5\uff1a\n\n
str.substr(start [, length])<\/code><\/pre>\n\n