用户输入的API查询

Question

I have a form where user types in the city name, I want to make an API call and get weather results in that city and then display it in the console.

I'm getting an error because for some reason the variable that holds input.value is not being concatenated into the string.

Here's the code:

var request;
var input1 = document.getElementById('city');
var api = 'https://api.openweathermap.org/data/2.5/weather?q=';
var apikey = '&APPID=433b12b793d7ebc17989745c069a540b';
var sum = api + input1.value + apikey;

function myFunction() {

  request = new XMLHttpRequest();

  request.open('GET', sum, true);
  request.onload = function() {

    var data = JSON.parse(this.response);
    if (request.status >= 200 && request.status < 400) {
      console.log(data);
    } else {
      console.log(input1.value);
    }
  }

  request.send();
}
myFunction(input1.value);

<input id='city' value='San Francisco'>

Thanks for any help!

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