puppeteer/assets/js/89c78f53.25a2e8b1.js

"use strict";(self.webpackChunkwebsite=self.webpackChunkwebsite||[]).push([[78530],{3905:(e,t,n)=>{n.d(t,{Zo:()=>s,kt:()=>d});var a=n(67294);function r(e,t,n){return t in e?Object.defineProperty(e,t,{value:n,enumerable:!0,configurable:!0,writable:!0}):e[t]=n,e}function i(e,t){var n=Object.keys(e);if(Object.getOwnPropertySymbols){var a=Object.getOwnPropertySymbols(e);t&&(a=a.filter((function(t){return Object.getOwnPropertyDescriptor(e,t).enumerable}))),n.push.apply(n,a)}return n}function o(e){for(var t=1;t<arguments.length;t++){var n=null!=arguments[t]?arguments[t]:{};t%2?i(Object(n),!0).forEach((function(t){r(e,t,n[t])})):Object.getOwnPropertyDescriptors?Object.defineProperties(e,Object.getOwnPropertyDescriptors(n)):i(Object(n)).forEach((function(t){Object.defineProperty(e,t,Object.getOwnPropertyDescriptor(n,t))}))}return e}function p(e,t){if(null==e)return{};var n,a,r=function(e,t){if(null==e)return{};var 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i=n.length,o=new Array(i);o[0]=m;var p={};for(var l in t)hasOwnProperty.call(t,l)&&(p[l]=t[l]);p.originalType=e,p.mdxType="string"==typeof e?e:r,o[1]=p;for(var u=2;u<i;u++)o[u]=n[u];return a.createElement.apply(null,o)}return a.createElement.apply(null,n)}m.displayName="MDXCreateElement"},91978:(e,t,n)=>{n.r(t),n.d(t,{assets:()=>l,contentTitle:()=>o,default:()=>c,frontMatter:()=>i,metadata:()=>p,toc:()=>u});var a=n(87462),r=(n(67294),n(3905));const i={},o="Page.waitForFunction() method",p={unversionedId:"api/puppeteer.page.waitforfunction",id:"api/puppeteer.page.waitforfunction",title:"Page.waitForFunction() method",description:"The waitForFunction can be used to observe viewport size change:",source:"@site/../docs/api/puppeteer.page.waitforfunction.md",sourceDirName:"api",slug:"/api/puppeteer.page.waitforfunction",permalink:"/api/puppeteer.page.waitforfunction",draft:!1,tags:[],version:"current",frontMatter:{},sidebar:"sidebar",previous:{title:"Page.waitForFrame() method",permalink:"/api/puppeteer.page.waitforframe"},next:{title:"Page.waitForNavigation() method",permalink:"/api/puppeteer.page.waitfornavigation"}},l={},u=[{value:"Parameters",id:"parameters",level:2}],s={toc:u};function c(e){let{components:t,...n}=e;return(0,r.kt)("wrapper",(0,a.Z)({},s,n,{components:t,mdxType:"MDXLayout"}),(0,r.kt)("h1",{id:"pagewaitforfunction-method"},"Page.waitForFunction() method"),(0,r.kt)("p",null,"The ",(0,r.kt)("inlineCode",{parentName:"p"},"waitForFunction")," can be used to observe viewport size change:"),(0,r.kt)("pre",null,(0,r.kt)("code",{parentName:"pre"},"const puppeteer = require('puppeteer');\n(async () => {\nconst browser = await puppeteer.launch();\nconst page = await browser.newPage();\nconst watchDog = page.waitForFunction('window.innerWidth < 100');\nawait page.setViewport({ width: 50, height: 50 });\nawait watchDog;\nawait browser.close();\n})();\n")),(0,r.kt)("p",null,"To pass arguments from node.js to the predicate of 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3000));\nimg.remove();\n},\n{},\nusername\n);\n")),(0,r.kt)("p",null,(0,r.kt)("strong",{parentName:"p"},"Signature:")),(0,r.kt)("pre",null,(0,r.kt)("code",{parentName:"pre",className:"language-typescript"},"waitForFunction<Params extends unknown[], Func extends EvaluateFunc<Params> = EvaluateFunc<Params>>(pageFunction: Func | string, options?: {\n        timeout?: number;\n        polling?: string | number;\n    }, ...args: Params): Promise<HandleFor<Awaited<ReturnType<Func>>>>;\n")),(0,r.kt)("h2",{id:"parameters"},"Parameters"),(0,r.kt)("table",null,(0,r.kt)("thead",{parentName:"table"},(0,r.kt)("tr",{parentName:"thead"},(0,r.kt)("th",{parentName:"tr",align:null},"Parameter"),(0,r.kt)("th",{parentName:"tr",align:null},"Type"),(0,r.kt)("th",{parentName:"tr",align:null},"Description"))),(0,r.kt)("tbody",{parentName:"table"},(0,r.kt)("tr",{parentName:"tbody"},(0,r.kt)("td",{parentName:"tr",align:null},"pageFunction"),(0,r.kt)("td",{parentName:"tr",align:null},"Func ","|"," 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This is the tightest polling mode which is suitable to observe styling changes.",(0,r.kt)("br",null)," - ",(0,r.kt)("inlineCode",{parentName:"p"},"mutation"),": to execute pageFunction on every DOM mutation.")),(0,r.kt)("li",{parentName:"ul"},(0,r.kt)("p",{parentName:"li"},(0,r.kt)("inlineCode",{parentName:"p"},"timeout"),": maximum time to wait for in milliseconds. Defaults to ",(0,r.kt)("inlineCode",{parentName:"p"},"30000")," (30 seconds). Pass ",(0,r.kt)("inlineCode",{parentName:"p"},"0")," to disable timeout. The default value can be changed by using the ",(0,r.kt)("a",{parentName:"p",href:"/api/puppeteer.page.setdefaulttimeout"},"page.setDefaultTimeout(timeout)")," method."))))}c.isMDXComponent=!0}}]);