关于javascript:js多个基本类型计算

let str=true+11+null+9+undefined+"javascript"+false+null+9+[]+[" "]计算str

console.log(true+11) //12console.log(12+null) //12console.log(12+9) //21console.log(21+undefined) //NaNconsole.log(NaN+"javascript") //"NaNjavascript"console.log("NaNjavascript" +false) //"NaNjavascriptfalse"console.log("NaNjavascriptfalse"+null) //"NaNjavascriptfalsenull"console.log("NaNjavascriptfalsenull"+9) //"NaNjavascriptfalsenull9"console.log("NaNjavascriptfalsenull9"+[]) //"NaNjavascriptfalsenull9"console.log("NaNjavascriptfalsenull9"+[" "] //"NaNjavascriptfalsenull9 "

Number()

console.log(Number("hello word")); //NaNconsole.log(Number("")); //0console.log(Number("000011")); //11console.log(Number("true")); //NaNconsole.log(Number(true)); //1console.log(parseInt([3,2,3])); //3console.log(parseFloat([1,2,3])); //1

数字,字符串计算

console.log(10 + "10"); //"1010"console.log("10" + "10"); //"1010"console.log(+"10"+ + "10"); //20console.log((+"10") + (+"10")); // 20console.log(-"10"+ 10); //0

js多个根本类型计算