{"id":522,"hash":"976136ac3d0928d3a491c7a0f3f973c674836034befbb5c4e7ed8e7502dbed47","pattern":"Angular exception: Can&#39;t bind to &#39;ngForIn&#39; since it isn&#39;t a known native property","full_message":"What am I doing wrong?\n\nimport {bootstrap, Component} from 'angular2/angular2'\n\n@Component({\n  selector: 'conf-talks',\n  template: `<div *ngFor=\"let talk in talks\">\n     {{talk.title}} by {{talk.speaker}}\n     <p>{{talk.description}}\n   </div>`\n})\nclass ConfTalks {\n  talks = [ {title: 't1', speaker: 'Brian', description: 'talk 1'},\n            {title: 't2', speaker: 'Julie', description: 'talk 2'}];\n}\n@Component({\n  selector: 'my-app',\n  directives: [ConfTalks],\n  template: '<conf-talks></conf-talks>'\n})\nclass App {}\nbootstrap(App, [])\n\nThe error is\n\nEXCEPTION: Template parse errors:\nCan't bind to 'ngForIn' since it isn't a known native property\n(\"<div [ERROR ->]*ngFor=\"let talk in talks\">","ecosystem":"npm","package_name":"angular","package_version":null,"solution":"I typed in instead of of in the ngFor expression.\n\nBefor 2-beta.17, it should be:\n\n<div *ngFor=\"#talk of talks\">\n\nAs of beta.17, use the let syntax instead of #. See the UPDATE further down for more info.\n\nNote that the ngFor syntax \"desugars\" into the following:\n\n<template ngFor #talk [ngForOf]=\"talks\">\n  <div>...</div>\n</template>\n\nIf we use in instead, it turns into\n\n<template ngFor #talk [ngForIn]=\"talks\">\n  <div>...</div>\n</template>\n\nSince ngForIn isn't an attribute directive with an input property of the same name (like ngIf), Angular then tries to see if it is a (known native) property of the template element, and it isn't, hence the error.\n\nUPDATE - as of 2-beta.17, use the let syntax instead of #.  This updates to the following:\n\n<div *ngFor=\"let talk of talks\">\n\nNote that the ngFor syntax \"desugars\" into the following:\n\n<template ngFor let-talk [ngForOf]=\"talks\">\n  <div>...</div>\n</template>\n\nIf we use in instead, it turns into\n\n<template ngFor let-talk [ngForIn]=\"talks\">\n  <div>...</div>\n</template>","confidence":0.95,"source":"stackoverflow","source_url":"https://stackoverflow.com/questions/34561168/angular-exception-cant-bind-to-ngforin-since-it-isnt-a-known-native-propert","votes":489,"created_at":"2026-04-19T04:51:17.799983+00:00","updated_at":"2026-04-19T04:51:17.799983+00:00"}