Im getting this compilation error in my Angular 2 app:
TS7015: Element implicitly has an 'any' type because index expression is not of type 'number'.
The piece of code causing it is:
getApplicationCount(state:string) {
return this.applicationsByState[state] ? this.applicationsByState[state].length : 0;
}
This however doesn't cause this error:
getApplicationCount(state:string) {
return this.applicationsByState[<any>state] ? this.applicationsByState[<any>state].length : 0;
}
This doesn't make any sense to me. I would like to solve it when defining the attributes the first time. At the moment I'm writing:
private applicationsByState: Array<any> = [];
But someone mentioned that the problem is trying to use a string type as index in an array and that I should use a map. But I'm not sure how to do that.
Thans for your help!
If you want a key/value data structure then don't use an array.
You can use a regular object:
private applicationsByState: { [key: string]: any[] } = {};
getApplicationCount(state: string) {
return this.applicationsByState[state] ? this.applicationsByState[state].length : 0;
}
Or you can use a Map:
private applicationsByState: Map<string, any[]> = new Map<string, any[]>();
getApplicationCount(state: string) {
return this.applicationsByState.has(state) ? this.applicationsByState.get(state).length : 0;
}
Not the OP's direct issue but for users encountering this error for libraries not under their control, one can suppress this error is by adding:
"suppressImplicitAnyIndexErrors": true,
to the tsconfig.json file.
I used this to get around it so I could use the window object.
//in js code somewhere
window.DataManager = "My Data Manager";
//in strict typescript file
let test = (window as { [key: string]: any })["DataManager"] as string;
console.log(test); //output= My Data Manager
