Q:

ionic2 phone call function show error: Unexpected token. A constructor, method, accessor, or property was expected

about.html here is html page
<ion-content>    
    <ion-fab center buttom>
      <button ion-fab color="light">
        <ion-icon name='call'></ion-icon>
      </button>
    </ion-fab>

    <!-- <a ion-button color="light" href="tel:1800889958">
    立即拨打
    </a>   -->  

</ion-content>

about.ts 
here is typescript page. I install call number plugin ald, and import to app.module.ts also.
error showing at 'this'
error message: unexpected token. A constructor, method , accessor, or property was expected.
import { Component } from '@angular/core';
import { CallNumber } from '@ionic-native/call-number';

@Component({
  selector: 'page-about',
  templateUrl: 'about.html'
})

export class AboutPage {

  constructor(private call: CallNumber) { }

  this.callNumber.callNumber("1800889958", true)
  .then(() => console.log('Launched dialer!'))
  .catch(() => console.log('Error launching dialer'));

}

CLI error show:
[09:56:04]  typescript: src/pages/about/about.ts, line: 14 
            Unexpected token. A constructor, method, accessor, or property was expected. 

      L14:    this.callNumber.callNumber("1800889958", true)
      L15:    .then(() => console.log('Launched dialer!'))

[09:56:04]  typescript: src/pages/about/about.ts, line: 18 
            Declaration or statement expected. 

A:

You must add CallNumber as a provider.
import { CallNumber } from '@ionic-native/call-number';

...

@NgModule({
  ...

  providers: [
    ...
    CallNumber
    ...
  ]
  ...
})
export class AppModule { }

And your about.ts should look something like this:
import { Component } from '@angular/core';
import { Platform } from 'ionic-angular';
import { CallNumber } from '@ionic-native/call-number';

@Component({
  selector: 'page-about',
  templateUrl: 'about.html'
})

export class AboutPage {

  constructor(private call: CallNumber, private platform: Platform) { 
     this.platform.ready().then(() => {
        this.callToNumber();
     });
  }

  private callToNumber() {
     this.call.callNumber("1800889958", true)
         .then(() => console.log('Launched dialer!'))
         .catch(() => console.log('Error launching dialer'));  
  }  

}

Check this line this.call.callNumber, you had this.callNumber.callNumber and that seems to be the issue.
Update:
Always wait to Platform.ready() promise when you want to use native functionallities, because if you try to do something with native apis before it will fail.

