ajax如何接受2进制数据,Ajax发送和接收二进制字节流数据的方法

HTML5 Ajax 2.0标准中，增强了Ajax的许多功能，包括发送FormData数据，上传数据进度条等诸多功能。但实际上，Ajax可以字节发送二进制数据。

发送二进制数据

var oReq = new XMLHttpRequest();

oReq.open("POST", url, true);

oReq.onload = function (oEvent) {

// Uploaded.

};

var blob = new Blob(['abc123'], {type: 'text/plain'});

oReq.send(blob);

或者

var myArray = new ArrayBuffer(512);

var longInt8View = new Uint8Array(myArray);

for (var i=0; i< longInt8View.length; i++) {

longInt8View[i] = i % 255;

}

var xhr = new XMLHttpRequest;

xhr.open("POST", url, false);

xhr.send(myArray);

接收二进制数据

var oReq = new XMLHttpRequest();

oReq.open("GET", "/myfile.png", true);

oReq.responseType = "arraybuffer";

oReq.onload = function (oEvent) {

var arrayBuffer = oReq.response; // Note: not oReq.responseText

if (arrayBuffer) {

var byteArray = new Uint8Array(arrayBuffer);

for (var i = 0; i < byteArray.byteLength; i++) {

}

}

};

oReq.send(null);

当然，如上设置只能是文本类型，如果是Blob类型，那么如下即可

var oReq = new XMLHttpRequest();

oReq.open("GET", "/myfile.png", true);

oReq.responseType = "arraybuffer";

oReq.onload = function(oEvent) {

var blob = new Blob([oReq.response], {type: "image/png"});

// ...

};

oReq.send();

或者

var oReq = new XMLHttpRequest();

oReq.open("GET", "/myfile.png", true);

oReq.responseType = "blob";

oReq.onload = function(oEvent) {

var blob = oReq.response;

// ...

};

oReq.send();

如果你使用的是旧版本的浏览器，那么加载二进制可以如下

function load_binary_resource(url) {

var req = new XMLHttpRequest();

req.open('GET', url, false);

//XHR binary charset opt by Marcus Granado 2006 [http://mgran.blogspot.com]

req.overrideMimeType('text/plain; charset=x-user-defined');

req.send(null);

if (req.status != 200) return '';

return req.responseText;

}

注意:x-user-defined告诉浏览器不要解析数据