angular - alert message using ionic2 -

when click register button ,if enter fields going regsuccess page got message fill required feilds.

but want show message alert using ionic2 , typescript.

html:

<button primary full (click)="register()" >register</button>      <p>{{regmsg}}</p> 

.ts file:

 register(){     var _this= this;      // this.submitattempt = true;      if(!this.registrationform.valid){        _this.regmsg = "enter required feilds";     }     else {         console.log("success!")         console.log(this.registrationform.value);         _this.navctrl.setroot(regthankyoupage);      } 

import { alertcontroller } 'ionic-angular'; // import alert controller  export class mycomponent {    regmsg: string;    constructor(public alertcontroller: alertcontroller) {}    showerrormsg(msg) {     let alert = this.alertctrl.create({       title: msg,       subtitle: '10% of battery remaining',       buttons: ['dismiss']     });     alert.present();   }    register(){     if (!this.registrationform.valid) {       this.regmsg = "enter required feilds";       console.log("form invalid");       this.showerrormsg(this.regmsg);     } else {       console.log("valid form");     }   }  }