currently I define my model classes in this way:
export class Company {
constructor(
public id?: number,
public name?: string,
public shortName?: string
) {}
}
The reason, why I use ? is that in this case I don't get an error that values for properties aren't provided if I want to assign an empty company object to a variable like this:
this.editDataItem = new Company();
Can I somehow avoid the use of ? in the model declaration? Or is this the right way if I want to assign an empty instance to a variable without declaring all the properties? Are there any best practices for this?
You can also do like this, It is in JS.
class Company {
constructor(
id = 0,
name = '',
shortName = ''
) {}
}
const company1 = new Company();
console.log(company1);In Typescript you can do this:
export class Company {
constructor(
public id: number = 0,
public name: string = '',
public shortName: string = ''
) {}
}
const company1 = new Company();
console.log(company1);
The above snippet will help you to set the default values even if they are not passed. It could be a better way to achieve this, ? accepts undefined as value.
The ? is just a shorthand for undefined.
To prevent a property being undefined you would need to set it on initialization either by passing values to the constructor or setting default values.
Depending on your use-case this is a perfectly valid and correct way to define a models property types.
You might as well change your class to:
export class Company {
id?: number;
name?: string;
shortName?: string;
constructor(
) {}
}
Now you still have public properties but they are undefined by default and there is no need to pass any values to the constructor.