Making HTTP GET Requests in JavaScript

透過Javascript實做Http 呼叫Api

var xhr = new XMLHttpRequest(); xhr.open('GET', "http://localhost:25959/api/login?Acc=123123&Pw=AA", true); xhr.send(); xhr.onreadystatechange = processRequest; function processRequest(e) { if (xhr.readyState == 4 && xhr.status == 200) { var response = JSON.parse(xhr.responseText); console.log(response.Acc); } }

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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