puppeteer/assets/js/9e142493.897b88ce.js

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puppeteer &gt; ExecutionContext &gt; evaluate",source:"@site/versioned_docs/version-10.1.0/puppeteer.executioncontext.evaluate.md",sourceDirName:".",slug:"/puppeteer.executioncontext.evaluate",permalink:"/puppeteer/docs/puppeteer.executioncontext.evaluate",editUrl:"https://github.com/facebook/puppeteer/edit/main/website/versioned_docs/version-10.1.0/puppeteer.executioncontext.evaluate.md",version:"10.1.0",frontMatter:{},sidebar:"version-10.1.0/docs",previous:{title:"puppeteer.executioncontext",permalink:"/puppeteer/docs/puppeteer.executioncontext"},next:{title:"puppeteer.executioncontext.evaluatehandle",permalink:"/puppeteer/docs/puppeteer.executioncontext.evaluatehandle"}},c=[{value:"ExecutionContext.evaluate() method",id:"executioncontextevaluate-method",children:[]},{value:"Parameters",id:"parameters",children:[]},{value:"Remarks",id:"remarks",children:[]},{value:"Example 1",id:"example-1",children:[]},{value:"Example 2",id:"example-2",children:[]},{value:"Example 3",id:"example-3",children:[]}],s={toc:c};function d(e){var t=e.components,n=(0,r.Z)(e,p);return(0,o.kt)("wrapper",(0,a.Z)({},s,n,{components:t,mdxType:"MDXLayout"}),(0,o.kt)("p",null,(0,o.kt)("a",{parentName:"p",href:"/puppeteer/docs/index"},"Home")," ",">"," ",(0,o.kt)("a",{parentName:"p",href:"/puppeteer/docs/puppeteer"},"puppeteer")," ",">"," ",(0,o.kt)("a",{parentName:"p",href:"/puppeteer/docs/puppeteer.executioncontext"},"ExecutionContext")," ",">"," ",(0,o.kt)("a",{parentName:"p",href:"/puppeteer/docs/puppeteer.executioncontext.evaluate"},"evaluate")),(0,o.kt)("h2",{id:"executioncontextevaluate-method"},"ExecutionContext.evaluate() method"),(0,o.kt)("b",null,"Signature:"),(0,o.kt)("pre",null,(0,o.kt)("code",{parentName:"pre",className:"language-typescript"},"evaluate<ReturnType extends any>(pageFunction: Function | string, ...args: unknown[]): Promise<ReturnType>;\n")),(0,o.kt)("h2",{id:"parameters"},"Parameters"),(0,o.kt)("table",null,(0,o.kt)("thead",{parentName:"table"},(0,o.kt)("tr",{parentName:"thead"},(0,o.kt)("th",{parentName:"tr",align:null},"Parameter"),(0,o.kt)("th",{parentName:"tr",align:null},"Type"),(0,o.kt)("th",{parentName:"tr",align:null},"Description"))),(0,o.kt)("tbody",{parentName:"table"},(0,o.kt)("tr",{parentName:"tbody"},(0,o.kt)("td",{parentName:"tr",align:null},"pageFunction"),(0,o.kt)("td",{parentName:"tr",align:null},"Function ","|"," string"),(0,o.kt)("td",{parentName:"tr",align:null},"a function to be evaluated in the ",(0,o.kt)("code",null,"executionContext"))),(0,o.kt)("tr",{parentName:"tbody"},(0,o.kt)("td",{parentName:"tr",align:null},"args"),(0,o.kt)("td",{parentName:"tr",align:null},"unknown","[","]"),(0,o.kt)("td",{parentName:"tr",align:null},"argument to pass to the page function")))),(0,o.kt)("b",null,"Returns:"),(0,o.kt)("p",null,"Promise","<","ReturnType",">"),(0,o.kt)("p",null,"A promise that resolves to the return value of the given function."),(0,o.kt)("h2",{id:"remarks"},"Remarks"),(0,o.kt)("p",null,"If the function passed to the ",(0,o.kt)("inlineCode",{parentName:"p"},"executionContext.evaluate")," returns a Promise, then ",(0,o.kt)("inlineCode",{parentName:"p"},"executionContext.evaluate")," would wait for the promise to resolve and return its value. 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