Javascript Angular 2 http响应中的更改值不影响页面

我对angular 2很陌生。我试图在收到http请求的响应后更改该值，该参数将在页面中使用。我不明白为什么即使控制台日志中的值已更改，它也不会影响页面

page.html

---

当您使用

功能

时，您将丢失

类

的当前

此

。您应该在可观察的

success

和

error

功能中使用箭头功能<代码>函数（）{}应该是

（）=>{}

testMsg = 'before request';
enabled() {
    let body = JSON.parse(this._settingService.load(this.pageName));
    let url = this._settingService.loadUrl(this.pageName);
    this._sesService.getCarsRestful().subscribe(
        //changed to arrow function
        (response) => {
            console.log("Success Response" + response);
            this.test2 = response;
            // this.showFrame = 'show';
            // console.log(this.showFrame);
            this.testMsg = 'after request';
            console.log(this.testMsg);
        },
        //changed to arrow function
        (error) => { console.log("Error happened" + error) },
        //changed to arrow function
        () => {
            console.log("the subscription is completed");
            // console.log(this.test2[0].name);
            // this.showFrame = 'show';
        }
    );
}

---

当您使用

功能

时，您将丢失

类

的当前

此

。您应该在可观察的

success

和

error

功能中使用箭头功能<代码>函数（）{}应该是

（）=>{}

testMsg = 'before request';
enabled() {
    let body = JSON.parse(this._settingService.load(this.pageName));
    let url = this._settingService.loadUrl(this.pageName);
    this._sesService.getCarsRestful().subscribe(
        //changed to arrow function
        (response) => {
            console.log("Success Response" + response);
            this.test2 = response;
            // this.showFrame = 'show';
            // console.log(this.showFrame);
            this.testMsg = 'after request';
            console.log(this.testMsg);
        },
        //changed to arrow function
        (error) => { console.log("Error happened" + error) },
        //changed to arrow function
        () => {
            console.log("the subscription is completed");
            // console.log(this.test2[0].name);
            // this.showFrame = 'show';
        }
    );
}

testMsg = 'before request';
enabled() {
    let body = JSON.parse(this._settingService.load(this.pageName));
    let url = this._settingService.loadUrl(this.pageName);
    this._sesService.getCarsRestful().subscribe(
        //changed to arrow function
        (response) => {
            console.log("Success Response" + response);
            this.test2 = response;
            // this.showFrame = 'show';
            // console.log(this.showFrame);
            this.testMsg = 'after request';
            console.log(this.testMsg);
        },
        //changed to arrow function
        (error) => { console.log("Error happened" + error) },
        //changed to arrow function
        () => {
            console.log("the subscription is completed");
            // console.log(this.test2[0].name);
            // this.showFrame = 'show';
        }
    );
}