javascript判断是否支持WebAssembly
function iswebasm(){
var useWasm = 0;
var webAsmObj = window["WebAssembly"];
if (typeof webAsmObj === "object")
{
if (typeof webAsmObj["Memory"] === "function")
{
if ((typeof webAsmObj["instantiateStreaming"] === "function") || (typeof webAsmObj["instantiate"] === "function"))
useWasm = 1;
}
}
}