{"id":223,"date":"2026-03-07T23:51:00","date_gmt":"2026-03-07T15:51:00","guid":{"rendered":"https:\/\/www.resilence.cn\/?p=223"},"modified":"2026-03-07T23:51:00","modified_gmt":"2026-03-07T15:51:00","slug":"day-3-%e6%9d%a1%e4%bb%b6%e5%88%a4%e6%96%ad","status":"publish","type":"post","link":"https:\/\/www.resilence.cn\/?p=223","title":{"rendered":"Day-3-\u6761\u4ef6\u5224\u65ad"},"content":{"rendered":"<h1>Day 3: \u6761\u4ef6\u5224\u65ad<\/h1>\n<h2>\ud83c\udfaf \u5b66\u4e60\u76ee\u6807<\/h2>\n<ul>\n<li>\u7406\u89e3\u6761\u4ef6\u5224\u65ad\u7684\u6982\u5ff5\u548c\u4f5c\u7528<\/li>\n<li>\u638c\u63e1 if\/else \u8bed\u53e5\u7684\u4f7f\u7528<\/li>\n<li>\u5b66\u4f1a\u4f7f\u7528\u903b\u8f91\u8fd0\u7b97\u7b26<\/li>\n<li>\u638c\u63e1 switch \u8bed\u53e5<\/li>\n<li>\u4e86\u89e3\u4e09\u5143\u8fd0\u7b97\u7b26<\/li>\n<\/ul>\n<h2>\ud83d\udca1 \u6838\u5fc3\u6982\u5ff5<\/h2>\n<h3>\u4ec0\u4e48\u662f\u6761\u4ef6\u5224\u65ad\uff1f<\/h3>\n<p>\u6761\u4ef6\u5224\u65ad\u8ba9\u7a0b\u5e8f\u80fd\u591f\u6839\u636e\u4e0d\u540c\u7684\u60c5\u51b5\u6267\u884c\u4e0d\u540c\u7684\u4ee3\u7801\u3002\u5c31\u50cf\u73b0\u5b9e\u751f\u6d3b\u4e2d\uff1a<\/p>\n<ul>\n<li>&quot;\u5982\u679c\u4e0b\u96e8\uff0c\u5e26\u4f1e\uff1b\u5426\u5219\uff0c\u4e0d\u5e26&quot;<\/li>\n<li>&quot;\u5982\u679c\u5206\u6570&gt;=60\uff0c\u53ca\u683c\uff1b\u5426\u5219\uff0c\u4e0d\u53ca\u683c&quot;<\/li>\n<\/ul>\n<h3>\u4e3a\u4ec0\u4e48\u9700\u8981\u6761\u4ef6\u5224\u65ad\uff1f<\/h3>\n<pre><code class=\"language-javascript\">\/\/ \u6ca1\u6709\u6761\u4ef6\u5224\u65ad\nlet price = 100;\nlet finalPrice = price - 20;  \/\/ \u56fa\u5b9a\u6298\u6263\uff0c\u4e0d\u5408\u7406\n\n\/\/ \u6709\u6761\u4ef6\u5224\u65ad\nlet price = 100;\nlet finalPrice;\nif (price &gt; 50) {\n    finalPrice = price - 20;  \/\/ \u6ee150\u51cf20\n} else {\n    finalPrice = price - 5;   \/\/ \u5426\u5219\u51cf5\n}\n<\/code><\/pre>\n<h2>\ud83d\udcdd if \u8bed\u53e5<\/h2>\n<h3>\u57fa\u672c\u8bed\u6cd5<\/h3>\n<pre><code class=\"language-javascript\">if (\u6761\u4ef6) {\n    \/\/ \u6761\u4ef6\u4e3a true \u65f6\u6267\u884c\u7684\u4ee3\u7801\n}\n\nlet score = 85;\nif (score &gt;= 60) {\n    console.log(&quot;\u53ca\u683c\u4e86\uff01&quot;);\n}\n<\/code><\/pre>\n<h3>if&#8230;else \u8bed\u53e5<\/h3>\n<pre><code class=\"language-javascript\">if (\u6761\u4ef6) {\n    \/\/ \u6761\u4ef6\u4e3a true \u65f6\u6267\u884c\n} else {\n    \/\/ \u6761\u4ef6\u4e3a false \u65f6\u6267\u884c\n}\n\nlet score = 55;\nif (score &gt;= 60) {\n    console.log(&quot;\u53ca\u683c&quot;);\n} else {\n    console.log(&quot;\u4e0d\u53ca\u683c&quot;);\n}\n<\/code><\/pre>\n<h3>if&#8230;else if&#8230;else \u8bed\u53e5<\/h3>\n<pre><code class=\"language-javascript\">if (\u6761\u4ef61) {\n    \/\/ \u6761\u4ef61\u4e3a true \u65f6\u6267\u884c\n} else if (\u6761\u4ef62) {\n    \/\/ \u6761\u4ef62\u4e3a true \u65f6\u6267\u884c\n} else {\n    \/\/ \u6240\u6709\u6761\u4ef6\u90fd\u4e3a false \u65f6\u6267\u884c\n}\n\nlet score = 85;\nif (score &gt;= 90) {\n    console.log(&quot;\u4f18\u79c0&quot;);\n} else if (score &gt;= 80) {\n    console.log(&quot;\u826f\u597d&quot;);\n} else if (score &gt;= 60) {\n    console.log(&quot;\u53ca\u683c&quot;);\n} else {\n    console.log(&quot;\u4e0d\u53ca\u683c&quot;);\n}\n<\/code><\/pre>\n<h2>\ud83d\udd00 \u903b\u8f91\u8fd0\u7b97\u7b26<\/h2>\n<h3>1. &amp;&amp;\uff08\u4e0e\u8fd0\u7b97\uff09<\/h3>\n<p>\u4e24\u4e2a\u6761\u4ef6\u90fd\u4e3a true\uff0c\u7ed3\u679c\u624d\u4e3a true\u3002<\/p>\n<pre><code class=\"language-javascript\">let age = 25;\nlet hasLicense = true;\n\nif (age &gt;= 18 &amp;&amp; hasLicense) {\n    console.log(&quot;\u53ef\u4ee5\u5f00\u8f66&quot;);\n}\n<\/code><\/pre>\n<p><strong>\u771f\u503c\u8868<\/strong>\uff1a<\/p>\n<pre><code>true  &amp;&amp; true  = true\ntrue  &amp;&amp; false = false\nfalse &amp;&amp; true  = false\nfalse &amp;&amp; false = false\n<\/code><\/pre>\n<h3>2. ||\uff08\u6216\u8fd0\u7b97\uff09<\/h3>\n<p>\u81f3\u5c11\u6709\u4e00\u4e2a\u6761\u4ef6\u4e3a true\uff0c\u7ed3\u679c\u5c31\u4e3a true\u3002<\/p>\n<pre><code class=\"language-javascript\">let age = 65;\nlet isDisabled = false;\n\nif (age &gt;= 65 || isDisabled) {\n    console.log(&quot;\u53ef\u4ee5\u7533\u8bf7\u4f18\u60e0&quot;);\n}\n<\/code><\/pre>\n<p><strong>\u771f\u503c\u8868<\/strong>\uff1a<\/p>\n<pre><code>true  || true  = true\ntrue  || false = true\nfalse || true  = true\nfalse || false = false\n<\/code><\/pre>\n<h3>3. !\uff08\u975e\u8fd0\u7b97\uff09<\/h3>\n<p>\u53d6\u53cd\u3002<\/p>\n<pre><code class=\"language-javascript\">let isLoggedIn = false;\n\nif (!isLoggedIn) {\n    console.log(&quot;\u8bf7\u5148\u767b\u5f55&quot;);\n}\n<\/code><\/pre>\n<h2>\ud83c\udfaf \u6bd4\u8f83\u8fd0\u7b97\u7b26<\/h2>\n<pre><code class=\"language-javascript\">\/\/ \u7b49\u4e8e\n5 == &quot;5&quot;    \/\/ true  (\u81ea\u52a8\u7c7b\u578b\u8f6c\u6362)\n5 === &quot;5&quot;   \/\/ false (\u4e25\u683c\u6bd4\u8f83)\n\n\/\/ \u4e0d\u7b49\u4e8e\n5 != &quot;5&quot;    \/\/ false\n5 !== &quot;5&quot;   \/\/ true\n\n\/\/ \u5927\u4e8e\n5 &gt; 3       \/\/ true\n5 &gt;= 5      \/\/ true\n\n\/\/ \u5c0f\u4e8e\n3 &lt; 5       \/\/ true\n5 &lt;= 5      \/\/ true\n<\/code><\/pre>\n<p><strong>\u91cd\u8981<\/strong>\uff1a\u603b\u662f\u4f7f\u7528 <code>===<\/code> \u548c <code>!==<\/code> \u8fdb\u884c\u6bd4\u8f83\uff01<\/p>\n<h2>\ud83d\udd04 switch \u8bed\u53e5<\/h2>\n<pre><code class=\"language-javascript\">let day = &quot;\u661f\u671f\u4e00&quot;;\n\nswitch (day) {\n    case &quot;\u661f\u671f\u4e00&quot;:\n        console.log(&quot;\u5de5\u4f5c\u65e5&quot;);\n        break;\n    case &quot;\u661f\u671f\u4e8c&quot;:\n        console.log(&quot;\u5de5\u4f5c\u65e5&quot;);\n        break;\n    case &quot;\u661f\u671f\u516d&quot;:\n    case &quot;\u661f\u671f\u65e5&quot;:\n        console.log(&quot;\u5468\u672b&quot;);\n        break;\n    default:\n        console.log(&quot;\u672a\u77e5&quot;);\n}\n<\/code><\/pre>\n<h2>\u26a1 \u4e09\u5143\u8fd0\u7b97\u7b26<\/h2>\n<pre><code class=\"language-javascript\">\/\/ \u8bed\u6cd5\n\u6761\u4ef6 ? \u503c1 : \u503c2\n\n\/\/ \u793a\u4f8b\nlet age = 20;\nlet status = age &gt;= 18 ? &quot;\u6210\u5e74&quot; : &quot;\u672a\u6210\u5e74&quot;;\n<\/code><\/pre>\n<h2>\ud83c\udfae \u5b9e\u6218\u793a\u4f8b<\/h2>\n<h3>\u793a\u4f8b1\uff1a\u767b\u5f55\u9a8c\u8bc1<\/h3>\n<pre><code class=\"language-javascript\">function login(username, password) {\n    if (!username || !password) {\n        return {success: false, message: &quot;\u8bf7\u8f93\u5165\u7528\u6237\u540d\u548c\u5bc6\u7801&quot;};\n    }\n    \n    if (username.length &lt; 3) {\n        return {success: false, message: &quot;\u7528\u6237\u540d\u81f3\u5c113\u4e2a\u5b57\u7b26&quot;};\n    }\n    \n    if (password.length &lt; 6) {\n        return {success: false, message: &quot;\u5bc6\u7801\u81f3\u5c116\u4e2a\u5b57\u7b26&quot;};\n    }\n    \n    return {success: true, message: &quot;\u767b\u5f55\u6210\u529f&quot;};\n}\n<\/code><\/pre>\n<h3>\u793a\u4f8b2\uff1a\u6210\u7ee9\u8bc4\u7ea7<\/h3>\n<pre><code class=\"language-javascript\">function getGrade(score) {\n    if (score &gt;= 90) return &quot;A&quot;;\n    if (score &gt;= 80) return &quot;B&quot;;\n    if (score &gt;= 70) return &quot;C&quot;;\n    if (score &gt;= 60) return &quot;D&quot;;\n    return &quot;F&quot;;\n}\n<\/code><\/pre>\n<h3>\u793a\u4f8b3\uff1a\u4ef7\u683c\u8ba1\u7b97\u5668<\/h3>\n<pre><code class=\"language-javascript\">function calculatePrice(price, quantity, memberLevel) {\n    let total = price * quantity;\n    let discount = 0;\n    \n    switch (memberLevel) {\n        case &quot;gold&quot;: discount = 0.2; break;\n        case &quot;silver&quot;: discount = 0.1; break;\n        case &quot;bronze&quot;: discount = 0.05; break;\n    }\n    \n    \/\/ \u6ee1\u51cf\u4f18\u60e0\n    if (total &gt;= 100) total -= 20;\n    else if (total &gt;= 50) total -= 10;\n    \n    return total * (1 - discount);\n}\n<\/code><\/pre>\n<h2>\u270d\ufe0f \u7ec3\u4e60\u4efb\u52a1<\/h2>\n<h3>\u7ec3\u4e601\uff1a\u6570\u5b57\u6bd4\u8f83<\/h3>\n<pre><code class=\"language-javascript\">function findMax(a, b, c) {\n    let max = a;\n    if (b &gt; max) max = b;\n    if (c &gt; max) max = c;\n    return max;\n}\n<\/code><\/pre>\n<h3>\u7ec3\u4e602\uff1a\u95f0\u5e74\u5224\u65ad<\/h3>\n<pre><code class=\"language-javascript\">function isLeapYear(year) {\n    if ((year % 4 === 0 &amp;&amp; year % 100 !== 0) || year % 400 === 0) {\n        return true;\n    }\n    return false;\n}\n<\/code><\/pre>\n<h3>\u7ec3\u4e603\uff1a\u6e38\u620f\u8bc4\u7ea7<\/h3>\n<pre><code class=\"language-javascript\">function getGameRating(age) {\n    if (age &lt; 6) return &quot;\u4f11\u95f2&quot;;\n    if (age &lt; 12) return &quot;\u513f\u7ae5&quot;;\n    if (age &lt; 16) return &quot;\u9752\u5c11\u5e74&quot;;\n    if (age &lt; 18) return &quot;\u6210\u4eba&quot;;\n    return &quot;\u9650\u5236\u7ea7&quot;;\n}\n<\/code><\/pre>\n<h2>\ud83c\udf93 \u4eca\u65e5\u6311\u6218<\/h2>\n<p><strong>\u9879\u76ee\uff1a\u77f3\u5934\u526a\u5200\u5e03\u6e38\u620f<\/strong><\/p>\n<pre><code class=\"language-javascript\">function playRPS(playerChoice) {\n    const choices = [&quot;\u77f3\u5934&quot;, &quot;\u526a\u5200&quot;, &quot;\u5e03&quot;];\n    const computerChoice = choices[Math.floor(Math.random() * 3)];\n    \n    if (playerChoice === computerChoice) {\n        return `\u5e73\u5c40\uff01\u90fd\u9009\u62e9\u4e86${playerChoice}`;\n    }\n    \n    if (\n        (playerChoice === &quot;\u77f3\u5934&quot; &amp;&amp; computerChoice === &quot;\u526a\u5200&quot;) ||\n        (playerChoice === &quot;\u526a\u5200&quot; &amp;&amp; computerChoice === &quot;\u5e03&quot;) ||\n        (playerChoice === &quot;\u5e03&quot; &amp;&amp; computerChoice === &quot;\u77f3\u5934&quot;)\n    ) {\n        return `\u4f60\u8d62\u4e86\uff01${playerChoice}\u80dc${computerChoice}`;\n    }\n    \n    return `\u4f60\u8f93\u4e86\uff01${computerChoice}\u80dc${playerChoice}`;\n}\n<\/code><\/pre>\n<h2>\ud83d\udca1 \u6700\u4f73\u5b9e\u8df5<\/h2>\n<h3>1. \u7b80\u5355\u6761\u4ef6\u7528\u4e09\u5143\u8fd0\u7b97\u7b26<\/h3>\n<pre><code class=\"language-javascript\">let max = a &gt; b ? a : b;\n<\/code><\/pre>\n<h3>2. \u590d\u6742\u6761\u4ef6\u7528\u53d8\u91cf<\/h3>\n<pre><code class=\"language-javascript\">let canDrive = age &gt; 18 &amp;&amp; hasLicense;\nlet isValid = !isSuspended &amp;&amp; hasInsurance;\nif (canDrive &amp;&amp; isValid) { }\n<\/code><\/pre>\n<h3>3. \u63d0\u524d\u8fd4\u56de<\/h3>\n<pre><code class=\"language-javascript\">function process(user) {\n    if (!user) return &quot;\u65e0\u7528\u6237&quot;;\n    if (!user.isActive) return &quot;\u672a\u6fc0\u6d3b&quot;;\n    if (!user.hasPermission) return &quot;\u65e0\u6743\u9650&quot;;\n    return &quot;\u5904\u7406\u6210\u529f&quot;;\n}\n<\/code><\/pre>\n<hr>\n<p><strong>\u5b66\u4e60\u65f6\u95f4<\/strong>: 2026-03-07 13:30<br \/>\n<strong>\u96be\u5ea6<\/strong>: \u2b50\u2b50\u2b50\u2606\u2606<br \/>\n<strong>\u9884\u8ba1\u7528\u65f6<\/strong>: 2-3 \u5c0f\u65f6<br \/>\n<strong>\u5173\u952e\u8bcd<\/strong>: \u6761\u4ef6\u5224\u65ad, if, switch, \u903b\u8f91\u8fd0\u7b97\u7b26<br \/>\n<strong>\u76f8\u5173\u6807\u7b7e<\/strong>: #03-\u63a7\u5236\u6d41<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Day 3: \u6761\u4ef6\u5224\u65ad \ud83c\udfaf \u5b66\u4e60\u76ee\u6807 \u7406\u89e3\u6761\u4ef6\u5224\u65ad\u7684\u6982\u5ff5\u548c\u4f5c\u7528 \u638c\u63e1 if\/else \u8bed\u53e5\u7684\u4f7f\u7528 \u5b66\u4f1a\u4f7f\u7528\u903b\u8f91 &#8230; <a title=\"Day-3-\u6761\u4ef6\u5224\u65ad\" class=\"read-more\" href=\"https:\/\/www.resilence.cn\/?p=223\" aria-label=\"\u7ee7\u7eed\u9605\u8bfbDay-3-\u6761\u4ef6\u5224\u65ad\">\u9605\u8bfb\u66f4\u591a<\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-223","post","type-post","status-publish","format-standard","hentry","category-studycoding"],"_links":{"self":[{"href":"https:\/\/www.resilence.cn\/index.php?rest_route=\/wp\/v2\/posts\/223","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.resilence.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.resilence.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.resilence.cn\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.resilence.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=223"}],"version-history":[{"count":1,"href":"https:\/\/www.resilence.cn\/index.php?rest_route=\/wp\/v2\/posts\/223\/revisions"}],"predecessor-version":[{"id":224,"href":"https:\/\/www.resilence.cn\/index.php?rest_route=\/wp\/v2\/posts\/223\/revisions\/224"}],"wp:attachment":[{"href":"https:\/\/www.resilence.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=223"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.resilence.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=223"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.resilence.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=223"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}