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Ismael Garcia
Ismael Garcia

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🔥🔥🔥 Copying object keys and values to a class.🔥🔥🔥

#javascript #typescript #vue

Coping the values of and object parameter to this in a class

  • At first I declare the type and default values for my class keys, but then I realize that I will need to set the values in the constructor again. So the first solution that I thought of was the fallowing: 
//typescript export default class Project { id: string = ""; name: string = ""; date_end: string = ""; description: string = ""; parent: number | null = null; //....MORE keys constructor(data?: any) { let self = this; if (data) { Object.getOwnPropertyNames(data).forEach(key =>{ self[key] = data[key].value }) } } }
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But this solution it seems to dirty and crazy so i try the fallowing :

export default class Project { id: string = ""; name: string = ""; date_end: string = ""; description: string = ""; parent: number | null = null; //....MORE keys constructor(data?: any) if (data) { Object.assign(this, data); }cover_image: direct_url_to_image.jpg } }
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So what is Object.assing(target,source) doing ?

  • Only copies enumerable and own properties from a source object to a target object.
  • It uses [[Get]] on the source and [[Set]] on the target.
  • It assigns properties versus just copying or defining new properties.

The other option for me would be doing, the fallowing :

export default class Project { constructor(data?: any){ if (data) { this.id: string = data.id; this.name: string = data.name; this.date_end: string = data.date_end; this.description: string = data.description; this.parent: number | null = data.parent; //....MORE keys } } }
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Please any opinion or suggestions, about this topic or what is the best or a better implementation of assigning key -> values from obj1 to obj2, are more than welcome.

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