for( var i=0; i<100; i++){ ????????document.write( String.fromCharCode(i));//將0-100的askii碼值在頁(yè)面中寫(xiě)出來(lái) }%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% var str = "" ; for( var i=0; i<100; i++){?????????str +=String.fromCharCode(i); } document.write(str);
這兩個(gè)for循環(huán)第二個(gè)會(huì)比第一個(gè)優(yōu)化一點(diǎn)嗎？為什么？
qq_唔叫咩_0
2018-05-01 20:42:26
