定义和未定义的角度布尔移位

Question

我正在使用angular和typescript，并且我在一些布尔值上获得了一个非常奇怪的结果，每个周期将其值从定义转换为未定义。

class AnsokanController{

    finnsNr: boolean = false;

    constructor(
        console.log('CTOR Start. finnsNr: ' + this.finnsNr);

        const ansokan = ansokanService.ansokan;
        if (!ansokan) {       
            return;
        } else {
            this.finnsNr = true;
        }

        console.log('CTOR end. finnsNr: ' + this.finnsNr);
    }
}   

class HanteraAnsokanController extends AnsokanController {  

//content emitted cause not relevant
}

// this view uses HanteraAnsokanController
     <ombud finns-nr="!vm.finnsNr">
     </ombud>

// Ombud directive declaration
      <input id="ort"   
             ng-disabled="vm.skaInaktiveras(vm.finnsNr)" />


// Ombud controller
    skaInaktiveras(finnsNr: boolean): boolean {
        console.log('finnsNr:  ' + finnsNr );
        if (finnsNr === true ) {
            return true;            
        }

        return false;
     }


 // Console log output
 CTOR Start. finnsNr: false
 CTOR end. finnsNr: true
 finnsNr:  false
 finnsNr:  undefined
 finnsNr:  false
 finnsNr:  undefined
 finnsNr:  false
 finnsNr:  undefined
 finnsNr:  false
 finnsNr:  undefined
 finnsNr:  false
 finnsNr:  undefined
 finnsNr:  false
 finnsNr:  undefined