Making HTTP POST Requests in JavaScript

透過Javascript實做Http 呼叫Api

var http = new XMLHttpRequest(); var url = "http://localhost:25959/api/login"; var params = "acc=123123&pw=0958113359"; http.open("POST", url, true); //Send the proper header information along with the request http.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); http.onreadystatechange = function() {//Call a function when the state changes. if(http.readyState == 4 && http.status == 200) { console.log(http.responseText); } } http.send(params);

readyState定義

Value	State	Description
0	UNSENT	The open method hasn't been called yet
1	OPENED	The send method has been called
2	HEADERS_RECEIVED	The send method has been called and the HTTP request has returned the status and headers
3	LOADING	The HTTP request response is being downloaded
4	DONE	Everything has completed

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