我需要创建一个函数来依次进行HTTP调用,以便将一个调用的响应转换为另一个调用,例如从第一个调用获取用户的IP地址,并使用该IP在第二个调用中注册用户。
演示代码:
registerUser(user: User) {
this.utility.getIpAddress()
.subscribe(data => {
this.ipAddress = data.ip;
});
const body = {
UserName: user.UserName,
Email: user.Email,
//...
UserIP: this.ipAddress,
}
return this.http.post(this.registerAPI, body);
}
import { switchMap } from 'rxjs/operators';
registerUser(user: User) {
return this.utility.getIpAddress().pipe(
switchMap(data => {
this.ipAddress = data.ip;
const body = {
UserName: user.UserName,
Email: user.Email,
UserIP: this.ipAddress,
};
return this.http.post(this.registerAPI, body);
})
)
}
RxJS <5.5:
import { switchMap } from 'rxjs/operators'; registerUser(user: User) { return this.utility.getIpAddress() .switchMap(data => { this.ipAddress = data.ip; const body = { UserName: user.UserName, Email: user.Email, UserIP: this.ipAddress, }; return this.http.post(this.registerAPI, body); }); }