Ajax-Web API的令牌请求

I'm doing some code here i need to send a request from javascript client with a username and a password to a web api. In this request i need to receive a token.

This is what i have now:

  var loginData = {
     grant_type: 'password',
      //Username and password are fill by the user in the text fields
     username: username, 
     password: password
 };

  $.ajax({
    type: 'POST',
    crossDomain: true,   //I'm having some problems with: Access-Control-Allow-Origin
    crossOrigin:true,
    contentType: "application/json",
    url: 'https://localhost:44380/Token',
    data: loginData
}).done(function (data) {
    self.user(data.userName);
    sessionStorage.setItem("Token", data.access_token);
}).fail("Error");

When i execute the client i receive erros related to Access-Control-Allow-Origin

No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'null' is therefore not allowed access. The response had HTTP status code 400.

And Cross origin requests are only supported for protocol schemes: http, data, chrome, chrome-extension, https, chrome-extension-resource.

Any ideas? I'm a rookie in web ...

I'm not sure if i'm doing the ajax request correctly...

You need to enabled cors in your project here's a link to help you

https://docs.microsoft.com/en-us/aspnet/web-api/overview/security/enabling-cross-origin-requests-in-web-api

Add web.config

  <system.webServer>
    <httpProtocol>
      <customHeaders>
        <add name="Access-Control-Allow-Origin" value="http://[your service domain]" />
        <add name="Access-Control-Allow-Methods" value="*" />
        <add name="Access-Control-Allow-Headers" value="Origin, X-Requested-With, Content-Type, Accept, Authorization"/>
        <add name="Access-Control-Allow-Credentials" value="true"/>
      </customHeaders>
    </httpProtocol>
  </system.webServer>

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