2 var img = new Image(); 3 var start = new Date().getTime(); 4 img.src = "http://" + ip + "?t=" + start; 5 var flag = false ; // 无法访问 6 img.onload = function (){ 7 flag = true ; 8 console.log('ok' ); 9 }; 10 img.onerror = function (){ 11 flag = true ; 12 console.log('ok' ); 13 }; 14 var timer = setTimeout( function (){ 15 if (!flag){ // 如果真的无法访问 16 flag = false ; 17 console.log('failed' ); 18 } 19 },1500 ); 20 } 21 ping('192.168.1.10')