{"id":13265,"date":"2023-11-17T19:45:36","date_gmt":"2023-11-17T11:45:36","guid":{"rendered":"https:\/\/92it.top\/?p=13265"},"modified":"2023-11-17T19:45:36","modified_gmt":"2023-11-17T11:45:36","slug":"%e7%bd%91%e9%a1%b5-js-%e8%b0%83%e8%af%95%e6%8a%80%e5%b7%a7","status":"publish","type":"post","link":"https:\/\/92it.top\/?p=13265","title":{"rendered":"\u7f51\u9875 JS \u8c03\u8bd5\u6280\u5de7"},"content":{"rendered":"\n

debugger<\/strong><\/p>\n\n\n\n

\n\n\n\n

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\u793a\u4f8b\u4ee3\u7801\uff1a<\/p>\n\n\n\n

function a() {\n  let a_var = 'a';\n  b(a_var);\n}\n\nfunction b(a_var_from_a) {\n  debugger;\n  console.log(global_var);\n  let b_var = 'b';\n  c();\n}\n\nfunction c() {\n  let c_var = 'c';\n}\n\nlet module_var = 'module';\nvar global_var = 'global';\n\na();<\/pre>\n\n\n\n
\u6574\u4f53\u5c31\u662f\u8c03\u7528 a\uff0c\u7136\u540e a \u8c03\u7528 b\uff0cb \u8c03\u7528 c\uff0c\u7136\u540e\u6709\u5404\u79cd\u4f5c\u7528\u57df\u7684\u53d8\u91cf\u3002<\/p>\n\n\n\n
\u8bb0\u5f97\u6253\u5f00\u5f00\u53d1\u8005\u5de5\u5177\u9762\u677f\uff0c\u6ca1\u6253\u5f00\u7684\u8bdd\uff0cdebugger \u4f1a\u9759\u9ed8\u5931\u8d25\u3002<\/p>\n\n\n\n
\u4e0b\u9762\u662f\u65ad\u70b9\u540e\u7684\u6837\u5b50\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
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\u624b\u52a8\u6253\u65ad\u70b9<\/strong><\/p>\n\n\n\n
\n\n\n\n
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\"\"<\/figure><\/div>\n\n\n\n
\u5237\u65b0\u9875\u9762\u540e\uff0c\u624b\u52a8\u6253\u7684\u65ad\u70b9\u8fd8\u4f1a\u4fdd\u7559\u3002<\/p>\n\n\n\n
\u8c03\u7528\u6808\u4fe1\u606f<\/strong><\/p>\n\n\n\n
\n\n\n\n
\u9996\u5148\u662f\u51fd\u6570\u8c03\u7528\u6808\u4fe1\u606f\u3002<\/p>\n\n\n\n
\"\"<\/figure>\n\n\n\n
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\"\"<\/p>\n\n\n\n
\u4f5c\u7528\u57df<\/strong><\/p>\n\n\n\n
\n\n\n\n
\u6211\u4eec\u770b\u770b\u67d0\u4e2a\u51fd\u6570\u7684\u51fd\u6570\u4f5c\u7528\u57df\u7684\u4e0a\u4e0b\u6587\u3002<\/p>\n\n\n\n
\u627e\u5230 Scope \u8fd9\u4e2a\u6807\u7b7e\u9875\uff0c\u76ee\u524d\u6211\u4eec\u53ef\u4ee5\u770b\u5230\u6709\u4e09\u79cd\u7c7b\u578b\uff1aLocal\u3001Script \u548c Global\u3002<\/p>\n\n\n\n
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\u6700\u540e\u662f Global\uff0c\u5168\u5c40\u4f5c\u7528\u57df\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
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\"\"<\/figure><\/div>\n\n\n\n
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\u5f53\u7136\u9664\u4e86\u8fd9\u4e9b\uff0c\u8fd8\u6709\u4e0d\u5c11\uff0c\u6bd4\u5982\u5757\u4f5c\u7528\u57df\uff08Block\uff09\u3001\u6355\u83b7\u4f5c\u7528\u57df\uff08Catch Block\uff09\u3001Eval \u4f5c\u7528\u57df\u3001With \u5757\u4f5c\u7528\u57df\u7b49\uff0c\u7bc7\u5e45\u539f\u56e0\uff0c\u4e0d\u4e00\u4e00\u4ecb\u7ecd\u4e86\u3002<\/p>\n\n\n\n
\u6267\u884c\u4e0b\u4e00\u6b65<\/strong><\/p>\n\n\n\n
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\u6d4f\u89c8\u5668\u63d0\u4f9b\u4e86\u5404\u79cd\u6267\u884c\u4e0b\u4e00\u6b65\u4ee3\u7801\u7684\u65b9\u5f0f\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
\u6211\u4eec\u4e00\u4e2a\u4e2a\u8fc7\u4e00\u904d\u3002<\/p>\n\n\n\n
Resume \u6062\u590d\u811a\u672c\u6267\u884c<\/strong><\/p>\n\n\n\n
\u9996\u5148\u662f\u6700\u5de6\u8fb9\u8fd9\u4e2a \u77e9\u5f62+\u4e09\u89d2\u5f62 \u7684\u84dd\u8272\u6309\u94ae\uff0c\u5b83\u8868\u793a \u7ed3\u675f\u5f53\u524d\u65ad\u70b9<\/strong>\uff0c\u6062\u590d\u811a\u672c\u8fd0\u884c\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
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todoItems.forEach(item => {\n  \/\/ item \u4e0d\u53ef\u80fd\u4e3a null\uff0c\u6211\u4eec\u6765\u770b\u770b\u53d1\u751f\u751a\u4e48\u4e8b\u4e86\n  if (!item) {\n    debugger;\n  }\n  \/\/ ...\n})<\/pre>\n\n\n\n
Step over \u8df3\u8fc7\u4e0b\u4e00\u4e2a\u51fd\u6570<\/strong><\/p>\n\n\n\n
\u7136\u540e\u662f\u8df3\u8fc7\u4e0b\u4e00\u4e2a\u51fd\u6570\u3002\u5c31\u662f\u9047\u5230\u4e0b\u4e00\u4e2a\u8981\u6267\u884c\u7684\u51fd\u6570\uff0c\u5c31\u4e0d\u8fdb\u53bb\u4e86\uff0c\u6267\u884c\u5b8c\u5b83\u7ee7\u7eed\u5f80\u4e0b\u8fd0\u884c\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
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\u5982\u679c\u6211\u4eec\u53ea\u662f\u60f3\u770b\u5f53\u524d\u51fd\u6570\u7684\u5b8c\u6574\u903b\u8f91\uff0c\u90a3\u5c31\u8df3\u8fc7\u5176\u4e0b\u7684\u51fd\u6570\u6267\u884c\u3002<\/p>\n\n\n\n
Step into \u8fdb\u5165\u4e0b\u4e00\u4e2a\u51fd\u6570<\/strong><\/p>\n\n\n\n
\u5982\u679c\u8d70\u7740\u8d70\u7740\u9047\u5230\u4e00\u4e2a\u51fd\u6570\uff0c\u8fdb\u5165\u8fd9\u4e2a\u51fd\u6570\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
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Step out \u8df3\u51fa\u5f53\u524d\u51fd\u6570<\/strong><\/p>\n\n\n\n
\u5982\u679c\u4f60\u4e0d\u60f3\u518d\u770b\u5f53\u524d\u51fd\u6570\u7684\u6267\u884c\u4e86\uff0c\u60f3\u56de\u5230\u8c03\u7528\u5b83\u7684\u51fd\u6570\uff0c\u5c31\u53ef\u4ee5\u9009\u62e9\u8fd9\u4e2a\u65b9\u5f0f\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
Step \u4e0b\u4e00\u6b65<\/strong><\/p>\n\n\n\n
\u5c31\u662f\u666e\u901a\u7684\u4e0b\u4e00\u6b65\uff0c\u5b83\u4f1a\u4e25\u683c\u9075\u5b88\u4ee3\u7801\u7684\u6267\u884c\u987a\u5e8f\uff0c\u6bd4\u8f83\u5e38\u7528\u3002<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
Step into \u548c Step \u7684\u533a\u522b<\/strong><\/p>\n\n\n\n
Step into \u548c Step \u5728\u5927\u4f53\u7684\u8868\u73b0\u4e0a\u6709\u4e9b\u76f8\u540c\uff0c\u9047\u5230\u51fd\u6570\u662f\u4f1a\u8fdb\u5165\u51fd\u6570\u5185\u90e8\u7684\uff0c\u4f46\u5728\u5f02\u6b65\u4ee3\u7801\u4e0b\uff0c\u884c\u4e3a\u6709\u4e00\u4e9b\u4e0d\u540c<\/strong>\u3002<\/p>\n\n\n\n
Step into \u5728\u9047\u5230\u4e00\u4e2a\u5f02\u6b65\u4ee3\u7801\u7684\u56de\u8c03\u51fd\u6570\uff0c\u4f1a\u76f4\u63a5\u6302\u8d77\u5e76\u8ba9\u540e\u9762\u7684\u540c\u6b65\u4ee3\u7801\u7ee7\u7eed\u8dd1\uff0c\u76f4\u5230\u8fd9\u4e2a\u5f02\u6b65\u51fd\u6570\u88ab\u6267\u884c\uff0c\u7136\u540e\u8fdb\u5165\u8fd9\u4e2a\u51fd\u6570\u3002<\/p>\n\n\n\n
\u800c Step \u5219\u7b26\u5408\u4ee3\u7801\u7684\u6267\u884c\u987a\u5e8f\uff0c\u5148\u6267\u884c\u540e\u9762\u7684\u540c\u6b65\u4ee3\u7801\uff0c\u7136\u540e\u518d\u6267\u884c\u5f02\u6b65\u51fd\u6570\u3002<\/p>\n\n\n\n
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