{"id":392,"date":"2023-03-17T15:33:25","date_gmt":"2023-03-17T15:33:25","guid":{"rendered":"https:\/\/yunshangtulv.com.cn\/?p=392"},"modified":"2023-03-17T15:33:25","modified_gmt":"2023-03-17T15:33:25","slug":"%e5%88%a4%e6%96%ad%e8%af%ad%e5%8f%a5%e8%af%a6%e8%a7%a3%e5%8f%8a%e5%ba%94%e7%94%a8%e4%b8%be%e4%be%8b","status":"publish","type":"post","link":"https:\/\/yunshangtulv.com.cn\/?p=392","title":{"rendered":"\u5224\u65ad\u8bed\u53e5\u8be6\u89e3\u53ca\u5e94\u7528\u4e3e\u4f8b"},"content":{"rendered":"

R\u8bed\u8a00\u4e2d\u7684\u5224\u65ad\u8bed\u53e5\u4e3b\u8981\u6709if<\/code>\u8bed\u53e5\u548cswitch<\/code>\u8bed\u53e5\u3002if<\/code>\u8bed\u53e5\u53ef\u4ee5\u6839\u636e\u6307\u5b9a\u6761\u4ef6\u7684\u771f\u5047\u51b3\u5b9a\u7a0b\u5e8f\u7684\u6267\u884c\u6d41\u7a0b\uff0c\u800cswitch<\/code>\u8bed\u53e5\u5219\u53ef\u4ee5\u6839\u636e\u4e0d\u540c\u7684\u53d6\u503c\u8fdb\u884c\u5206\u652f\u5904\u7406\u3002\u4e0b\u9762\u6211\u4eec\u6765\u8be6\u7ec6\u4e86\u89e3\u4e00\u4e0b\u5b83\u4eec\u7684\u7528\u6cd5\u53ca\u5e94\u7528\u5b9e\u4f8b\u3002<\/p>\n

if\u8bed\u53e5<\/h2>\n

if\u8bed\u53e5\u7684\u4e00\u822c\u5f62\u5f0f\u4e3a\uff1a<\/p>\n

\n
if<\/span> (<\/span>condition)<\/span> {<\/span>
\n statement1
\n}<\/span> else<\/span> {<\/span>
\n statement2
\n}<\/span>
\n<\/code><\/div>\n<\/div>\n

\u5176\u4e2dcondition<\/code>\u4e3a\u9700\u8981\u5224\u65ad\u7684\u6761\u4ef6\uff0c\u5982\u679ccondition<\/code>\u4e3a\u771f\uff0c\u5219\u6267\u884cstatement1<\/code>\uff0c\u5426\u5219\u6267\u884cstatement2<\/code>\u3002<\/p>\n

\u4f8b\u5982\uff0c\u4e0b\u9762\u7684\u4ee3\u7801\u5c55\u793a\u4e86\u4e00\u4e2a\u7b80\u5355\u7684if\u8bed\u53e5\u7684\u5e94\u7528\u5b9e\u4f8b\u3002\u5b83\u6839\u636e\u7528\u6237\u8f93\u5165\u7684\u5206\u6570\u5224\u65ad\u7528\u6237\u7684\u7b49\u7ea7\u3002<\/p>\n

\n
score <-<\/span> readline(<\/span>prompt=<\/span>\"\u8bf7\u8f93\u5165\u5206\u6570: \"<\/span>)<\/span>
\nscore <-<\/span> as.numeric<\/span>(<\/span>score)<\/span><\/p>\n

if<\/span> (<\/span>score >=<\/span> 90<\/span>)<\/span> {<\/span>
\n cat(<\/span>\"\u60a8\u7684\u7b49\u7ea7\u662fA\\n\"<\/span>)<\/span>
\n}<\/span> else<\/span> if<\/span> (<\/span>score >=<\/span> 80<\/span>)<\/span> {<\/span>
\n cat(<\/span>\"\u60a8\u7684\u7b49\u7ea7\u662fB\\n\"<\/span>)<\/span>
\n}<\/span> else<\/span> if<\/span> (<\/span>score >=<\/span> 70<\/span>)<\/span> {<\/span>
\n cat(<\/span>\"\u60a8\u7684\u7b49\u7ea7\u662fC\\n\"<\/span>)<\/span>
\n}<\/span> else<\/span> if<\/span> (<\/span>score >=<\/span> 60<\/span>)<\/span> {<\/span>
\n cat(<\/span>\"\u60a8\u7684\u7b49\u7ea7\u662fD\\n\"<\/span>)<\/span>
\n}<\/span> else<\/span> {<\/span>
\n cat(<\/span>\"\u60a8\u7684\u7b49\u7ea7\u662fE\\n\"<\/span>)<\/span>
\n}<\/span>
\n<\/code><\/div>\n<\/div>\n

\u8fd9\u4e2a\u7a0b\u5e8f\u9996\u5148\u901a\u8fc7readline()<\/code>\u51fd\u6570\u83b7\u53d6\u7528\u6237\u8f93\u5165\u7684\u5206\u6570\uff0c\u7136\u540e\u4f7f\u7528as.numeric()<\/code>\u51fd\u6570\u5c06\u5176\u8f6c\u6362\u6210\u6570\u503c\u7c7b\u578b\u3002\u7136\u540e\u6839\u636e\u4e0d\u540c\u7684\u5206\u6570\u6bb5\uff0c\u5224\u65ad\u7528\u6237\u7684\u7b49\u7ea7\uff0c\u5e76\u8f93\u51fa\u76f8\u5e94\u7684\u63d0\u793a\u4fe1\u606f\u3002<\/p>\n

switch\u8bed\u53e5<\/h2>\n

switch\u8bed\u53e5\u7684\u4e00\u822c\u5f62\u5f0f\u4e3a\uff1a<\/p>\n

\n
switch<\/span>(<\/span>EXPR,<\/span> case1,<\/span> case2,<\/span> case3,<\/span> ...)<\/span>
\n<\/code><\/div>\n<\/div>\n

\u5176\u4e2dEXPR<\/code>\u4e3a\u9700\u8981\u8fdb\u884c\u5224\u65ad\u7684\u8868\u8fbe\u5f0f\uff0ccase1<\/code>\u3001case2<\/code>\u3001case3<\/code>\u7b49\u4e3a\u4e0d\u540c\u7684\u53d6\u503c\u60c5\u51b5\u3002<\/p>\n

\u4f8b\u5982\uff0c\u4e0b\u9762\u7684\u4ee3\u7801\u5c55\u793a\u4e86\u4e00\u4e2a\u7b80\u5355\u7684switch\u8bed\u53e5\u7684\u5e94\u7528\u5b9e\u4f8b\u3002\u5b83\u6839\u636e\u7528\u6237\u8f93\u5165\u7684\u6570\u5b57\u9009\u62e9\u4e0d\u540c\u7684\u83dc\u5355\u3002<\/p>\n

\n
choice <-<\/span> readline(<\/span>prompt=<\/span>\"\u8bf7\u9009\u62e9\u83dc\u5355: \"<\/span>)<\/span>
\nchoice <-<\/span> as.numeric<\/span>(<\/span>choice)<\/span><\/p>\n

menu <-<\/span> switch<\/span>(<\/span>choice,<\/span>
\n \"\u725b\u8089\u9762\"<\/span>,<\/span>
\n \"\u9ebb\u8fa3\u70eb\"<\/span>,<\/span>
\n \"\u70e4\u4e32\"<\/span>,<\/span>
\n \"\u70b8\u9e21\"<\/span>,<\/span>
\n \"\u7092\u996d\"<\/span>)<\/span><\/p>\n

cat(<\/span>\"\u60a8\u9009\u62e9\u7684\u83dc\u5355\u662f\uff1a\"<\/span>,<\/span> menu,<\/span> \"\\n\"<\/span>)<\/span>
\n<\/code><\/div>\n<\/div>\n

\u8fd9\u4e2a\u7a0b\u5e8f\u9996\u5148\u901a\u8fc7readline()<\/code>\u51fd\u6570\u83b7\u53d6\u7528\u6237\u8f93\u5165\u7684\u6570\u5b57\uff0c\u7136\u540e\u4f7f\u7528as.numeric()<\/code>\u51fd\u6570\u5c06\u5176\u8f6c\u6362\u6210\u6570\u503c\u7c7b\u578b\u3002\u7136\u540e\u6839\u636e\u4e0d\u540c\u7684\u6570\u5b57\uff0c\u9009\u62e9\u76f8\u5e94\u7684\u83dc\u5355\uff0c\u5e76\u8f93\u51fa\u63d0\u793a\u4fe1\u606f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

R\u8bed\u8a00\u4e2d\u7684\u5224\u65ad\u8bed\u53e5\u4e3b\u8981\u6709if\u8bed\u53e5\u548cswitch\u8bed\u53e5\u3002if\u8bed\u53e5\u53ef\u4ee5\u6839\u636e\u6307\u5b9a\u6761\u4ef6\u7684\u771f\u5047\u51b3\u5b9a\u7a0b\u5e8f\u7684\u6267\u884c\u6d41\u7a0b\uff0c\u800cswi […]<\/p>\n","protected":false},"author":111,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-392","post","type-post","status-publish","format-standard","hentry","category-r"],"_links":{"self":[{"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=\/wp\/v2\/posts\/392","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=\/wp\/v2\/users\/111"}],"replies":[{"embeddable":true,"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=392"}],"version-history":[{"count":0,"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=\/wp\/v2\/posts\/392\/revisions"}],"wp:attachment":[{"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=392"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=392"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/yunshangtulv.com.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=392"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}