console
var a=10;
if(a>5){console.log("a比5大");}
var b=13
if(b>15)
{console.log("b比15大");}
else{console.log("b比15大");}
var book="maths";
if(book=="history")
{console.log("History Book");}
else if(book=="maths")
{console.log("Maths Book");}
else if(book=="economics")
{console.log("Economics Book");}
else{console.log("Unknown Book");}
var grade='A';
console.log("进入switch语句");
switch (grade)
{case 'A':console.log("供应商的评分为A!");
break;
case 'B':console.log("供应商的评分为B!");
break;
case 'C':console.log("供应商的评分为C!");
break;
case 'D':console.log("供应商的评分为D!");
break;
case 'F':console.log("供应商的评分为F,不及格,不建议继续合作!");
break;
default:console.log("供应商的评分未知,为其它值!");}
console.log("swtich语句完毕!");