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小开

最佳答案

var myImage = document.querySelector('img');


var myHeaders = new Headers();
myHeaders.append('pragma', 'no-cache');
myHeaders.append('cache-control', 'no-cache');


var myInit = {
method: 'GET',
headers: myHeaders,
};


var myRequest = new Request('myImage.jpg');


fetch(myRequest, myInit)
.then(function(response) {
return response.blob();
})
.then(function(response) {
var objectURL = URL.createObjectURL(response);
myImage.src = objectURL;
});

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>ES6</title>
</head>
<body>
<img src="">
</body>
</html>

小开

  // Download a resource with cache busting, to bypass the cache
// completely.
fetch("some.json", {cache: "no-store"})
.then(function(response) { /* consume the response */ });


// Download a resource with cache busting, but update the HTTP
// cache with the downloaded resource.
fetch("some.json", {cache: "reload"})
.then(function(response) { /* consume the response */ });


// Download a resource with cache busting when dealing with a
// properly configured server that will send the correct ETag
// and Date headers and properly handle If-Modified-Since and
// If-None-Match request headers, therefore we can rely on the
// validation to guarantee a fresh response.
fetch("some.json", {cache: "no-cache"})
.then(function(response) { /* consume the response */ });


// Download a resource with economics in mind!  Prefer a cached
// albeit stale response to conserve as much bandwidth as possible.
fetch("some.json", {cache: "force-cache"})
.then(function(response) { /* consume the response */ });

小开

return fetch(url, {
headers: {
'Cache-Control': 'no-cache'
}
}).then(function (res) {
return res.json();
}).catch(function(error) {
console.warn('Failed: ', error);
});

小开

  const URL = "http://example.com";
const ms = Date.now();
const data = await fetch(URL+"?dummy="+ms)
.catch(er => game_log(er.message))
.then(response => response.text());