js将4个字节型字符串转为Float

function convertFloat(byteStr) {
var buffer = str2ArrayBuffer(byteStr, 4);
var dataView = new DataView(buffer, 0, 4);
return dataView.getFloat32(0);
} // 字符串转为ArrayBuffer对象，参数为字符串
function str2ArrayBuffer(str, len) {
var buf = new ArrayBuffer(len);
var bufView = new Uint8Array(buf);
for (var i = 0, strLen = str.length; i < strLen; i++) {
bufView[i] = parseInt(str.substr(i * 2, 2), 16);
}
return buf;
}