https://gis.stackexchange.com/questions/278165/i-have-wkid-latestwkid-and-x-y-coordinates-i-need-lat-lng/295274#295274
https://sampleserver1.arcgisonline.com/ArcGIS/rest/services/Geometry/GeometryServer/project?inSR=26985&outSR=4326&geometries=%7B%0D%0A++%22geometryType%22+%3A+%22esriGeometryPoint%22%2C%0D%0A++%22geometries%22+%3A+%5B%0D%0A+++++%7B%0D%0A+++++++%22x%22+%3A+398747.6825%2C+%0D%0A+++++++%22y%22+%3A+136532.0785%0D%0A+++++%7D%0D%0A++%5D%0D%0A%7D&f=HTML
You could use the ArcGIS server REST endpoint to convert to wkid 4326 (lat/lon). Here's a URL for one of Esri's sample servers:
Pasting the coordinate in google maps gives you this (Littleton, right?):
If you just need to convert the occasional coordinate this will work fine, but I guess as soon as it's thousands of coordinates, you are going to want to automate stuff.
As for the meaning of latestWkid, see here: https://support.esri.com/en/technical-article/000013950
=============================
fix bug:
* bug fix:
* No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:10' is therefore not allowed access. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
++++++++++++++++++++++ good solution ++++++++++++++++++++++++++
use dataType: 'jsonp', works for me.
async function get_ajax_data(){
var _reprojected_lat_lng = await $.ajax({
type: 'GET',
dataType: 'jsonp',
data: {},
url: _reprojection_url,
error: function (jqXHR, textStatus, errorThrown) {
console.log(jqXHR)
},
success: function (data) {
console.log(data);
// note: data is already json type, you just specify dataType: jsonp
return data;
}
});
} // function
another way use fetch() not easy. bad solution
ff++++++++++++++++++++++++++++++++++++++++++++++++++
* https://stackoverflow.com/questions/43871637/no-access-control-allow-origin-header-is-present-on-the-requested-resource-whe
solution
const proxyurl = "https://cors-anywhere.herokuapp.com/";
const url = "https://example.com"; // site that doesn’t send Access-Control-*
fetch(proxyurl + url) // https://cors-anywhere.herokuapp.com/https://example.com
.then(response => response.text())
.then(contents => console.log(contents))
.catch(() => console.log("Can’t access " + url + " response. Blocked by browser?"))
*/
No 'Access-Control-Allow-Origin' header is present on the requested resource—when trying to get data from a REST API
How to use a CORS proxy to get around “No Access-Control-Allow-Origin header” problems
If you don’t control the server your frontend JavaScript code is sending a request to, and the problem with the response from that server is just the lack of the necessary
Access-Control-Allow-Origin header, you can still get things to work—by making the request through a CORS proxy. To show how that works, first here’s some code that doesn’t use a CORS proxy:const url = "https://example.com"; // site that doesn’t send Access-Control-*
fetch(url)
.then(response => response.text())
.then(contents => console.log(contents))
.catch(() => console.log("Can’t access " + url + " response. Blocked by browser?"))
The reason the
catch block gets hit there is, the browser prevents that code from accessing the response which comes back from https://example.com. And the reason the browser does that is, the response lacks the Access-Control-Allow-Origin response header.
Now, here’s exactly the same example but just with a CORS proxy added in:
const proxyurl = "https://cors-anywhere.herokuapp.com/";
const url = "https://example.com"; // site that doesn’t send Access-Control-*
fetch(proxyurl + url) // https://cors-anywhere.herokuapp.com/https://example.com
.then(response => response.text())
.then(contents => console.log(contents))
.catch(() => console.log("Can’t access " + url + " response. Blocked by browser?"))
Note: If https://cors-anywhere.herokuapp.com is down or unavailable when you try it, then see below for how to deploy your own CORS Anywhere server at Heroku in just 2-3 minutes.
The second code snippet above can access the response successfully because taking the request URL and changing it to https://cors-anywhere.herokuapp.com/https://example.com—by just prefixing it with the proxy URL—causes the request to get made through that proxy, which then:
- Forwards the request to
https://example.com. - Receives the response from
https://example.com. - Adds the
Access-Control-Allow-Originheader to the response. - Passes that response, with that added header, back to the requesting frontend code.
The browser then allows the frontend code to access the response, because that response with the
Access-Control-Allow-Origin response header is what the browser sees.
You can easily run your own proxy using code from https://github.com/Rob--W/cors-anywhere/.
You can also easily deploy your own proxy to Heroku in literally just 2-3 minutes, with 5 commands:
You can also easily deploy your own proxy to Heroku in literally just 2-3 minutes, with 5 commands:
git clone https://github.com/Rob--W/cors-anywhere.git
cd cors-anywhere/
npm install
heroku create
git push heroku master
After running those commands, you’ll end up with your own CORS Anywhere server running at, e.g., https://cryptic-headland-94862.herokuapp.com/. So then rather than prefixing your request URL with
https://cors-anywhere.herokuapp.com, prefix it instead with the URL for your own instance; e.g., https://cryptic-headland-94862.herokuapp.com/https://example.com.
So if when you go to try to use https://cors-anywhere.herokuapp.com, you find it’s down(which it sometimes will be), then consider getting a Heroku account (if you don’t already) and take 2 or 3 minutes to do the steps above to deploy your own CORS Anywhere server on Heroku.
Regardless, whether you run your own or use https://cors-anywhere.herokuapp.com or other open proxy, this solution will work even if the request is one that triggers browsers to do a CORS preflight
OPTIONS request—because in that case, the proxy also sends back the Access-Control-Allow-Headers and Access-Control-Allow-Methods headers needed to make the preflight successful.
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