Question

当我尝试使用带参数的类创建新实例时，我收到此错误，但是当不使用参数时，它可以正常工作。可能是什么问题？

这是班级

export class Recipe {
  public name: string;
  public  description: string;
  public  imageP: string;

  constructor(name1: string, description1: string, imagePath1: string) {
    this.name = name1;
    this.description = description1;
    this.imageP = imagePath1;
  }

}

这是组件

import {Component, OnInit, Output} from '@angular/core';
import { Recipe } from '../recipe';

@Component({
  selector: 'rb-recipes-list',
  templateUrl: './recipes-list.component.html',
  providers: [ Recipe ]
})
export class RecipesListComponent implements OnInit {

  theRecipe: Recipe = new Recipe( 'New', 'blah blah blah', 'ddkkkiskxmdks');

  recipe = this.theRecipe.name;

    constructor() { }

  ngOnInit() {
  }

}

如果我分别在recipe.ts和recipe-list.component.ts中这样做：

export class Recipe {
  public name: string = 'hello world';
  public  description: string = 'hello world';
  public  imageP: string = 'hello world'; 

}


import {Component, OnInit, Output} from '@angular/core';
import { Recipe } from '../recipe';

@Component({
  selector: 'rb-recipes-list',
  templateUrl: './recipes-list.component.html',
  providers: [ Recipe ]
})
export class RecipesListComponent implements OnInit {
  //recipes: Recipe[] = [];

  theRecipe: Recipe = new Recipe()

  recipe = this.theRecipe.name;

    constructor() { }

  ngOnInit() {
  }

}

完美无缺。

Answer 1

问题应该是此关键字

export class RecipesListComponent implements OnInit {

  theRecipe: Recipe = new Recipe( 'New', 'blah blah blah', 'ddkkkiskxmdks');

  // recipe = this.theRecipe.name;          //<<<===removed this line

  recipe = theRecipe.name;                  //<<===removed this keyword

}

更新：我刚刚对此进行了测试，效果很好。

export class RecipesListComponent implements OnInit {

    theRecipe:Recipe;

    constructor(){
      this.theRecipe = new Recipe( 'New', 'blah blah blah', 'ddkkkiskxmdks');
      console.log(this.theRecipe.name);
    }
  ....
}

OR

export class RecipesListComponent implements OnInit {

        theRecipe:Recipe;
        theRecipe = new Recipe( 'New', 'blah blah blah', 'ddkkkiskxmdks');
        constructor(){
           console.log(this.theRecipe.name);
        }
      ....
 }

注意即可。删除providers:[Recipe]（不需要）。你只需要导入它就可以在你想要的地方使用它。

Update1 ：我已经使用plunker对其进行了测试并且正常运行，

DEMO：https://plnkr.co/edit/Vxdeyjwdjol9TnVhCV19?p=preview 检查浏览器的控制台。

错误：无法解析Classname的所有参数（？??）

1 个答案: