puppeteer/assets/js/0f1d75c2.083448bb.js

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method",description:"Signature:",source:"@site/versioned_docs/version-15.3.0/api/puppeteer.executioncontext.evaluate.md",sourceDirName:"api",slug:"/api/puppeteer.executioncontext.evaluate",permalink:"/api/puppeteer.executioncontext.evaluate",draft:!1,tags:[],version:"15.3.0",frontMatter:{sidebar_label:"ExecutionContext.evaluate"},sidebar:"sidebar",previous:{title:"ExecutionContext",permalink:"/api/puppeteer.executioncontext"},next:{title:"ExecutionContext.evaluateHandle",permalink:"/api/puppeteer.executioncontext.evaluatehandle"}},p={},u=[{value:"Parameters",id:"parameters",level:2},{value:"Remarks",id:"remarks",level:2},{value:"Example 1",id:"example-1",level:2},{value:"Example 2",id:"example-2",level:2},{value:"Example 3",id:"example-3",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:"executioncontextevaluate-method"},"ExecutionContext.evaluate() method"),(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"},"class ExecutionContext {\n  evaluate<\n    Params extends unknown[],\n    Func extends EvaluateFunc<Params> = EvaluateFunc<Params>\n  >(\n    pageFunction: Func | string,\n    ...args: Params\n  ): Promise<Awaited<ReturnType<Func>>>;\n}\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 ","|"," string"),(0,r.kt)("td",{parentName:"tr",align:null},"a function to be evaluated in the ",(0,r.kt)("code",null,"executionContext"))),(0,r.kt)("tr",{parentName:"tbody"},(0,r.kt)("td",{parentName:"tr",align:null},"args"),(0,r.kt)("td",{parentName:"tr",align:null},"Params"),(0,r.kt)("td",{parentName:"tr",align:null},"argument to pass to the page function")))),(0,r.kt)("p",null,(0,r.kt)("strong",{parentName:"p"},"Returns:")),(0,r.kt)("p",null,"Promise","<","Awaited","<","ReturnType","<","Func",">",">",">"),(0,r.kt)("p",null,"A promise that resolves to the return value of the given function."),(0,r.kt)("h2",{id:"remarks"},"Remarks"),(0,r.kt)("p",null,"If the function passed to the ",(0,r.kt)("inlineCode",{parentName:"p"},"executionContext.evaluate")," returns a Promise, then ",(0,r.kt)("inlineCode",{parentName:"p"},"executionContext.evaluate")," would wait for the promise to resolve and return its value. If the function passed to the ",(0,r.kt)("inlineCode",{parentName:"p"},"executionContext.evaluate")," returns a non-serializable value, then ",(0,r.kt)("inlineCode",{parentName:"p"},"executionContext.evaluate")," resolves to ",(0,r.kt)("inlineCode",{parentName:"p"},"undefined"),". 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