1.4 KiB
1.4 KiB
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Promise Resolve |
Promise Resolve
Description
A Promise.resolve
function indicates the successful completion of a Promise. This function allows you to return a Promise to the calling function.
Promise.resolve
takes a single parameter to return to the calling function. This parameter can either be a value, a thenable, or another Promise.
A "value" for a resolve function can be basic JavaScript types, arrays, or objects.
Promise.resolve('success'); // string
Promise.resolve([2, 3, 5]); // array
Promise.resolve({name: 'John', age: '43'}); // object
A "thenable" is a function that takes two callback functions as parameters. You can use the first parameter to trigger a successful completion, and the second to return an error on the Promise.
thenableFunction = {then: function(onSuccesss, onFailure) {
if (condition === 'success') {
onSuccess(paramList); // success condition
} else {
onFailure(paramList); // error condition
}
}
}
Promise.resolve(thenableFunction);
Chaining a then function to a promise caller will give you access to the result of Promise.resolve
.
promiseCallingFunction(paramList)
.then(function(value) {
/*
* this is where you get access to the value
* returned by a promise on successful completion
*/
});