前端项目中会用到的一些快捷操作，下面的代码可以直接复制到控制台运行。数字舍入letfloatNum=100.5;letintNum=~~floatNum;console.log(intNum);//100字符串转数字letstr="10000";letnum=+str;console.log(num);//10000Falsy和TruthyValue转换booleanFalsy是Javascript中所有可以转化为false的值的统称，一共有8个：false本身、空字符串、null、undefined、NaN、数字0、数字-0、大数字0n。除Falsy值外的所有值均为TruthyletfalseNum=0;letfalseStr="";letfalseUndefined;letfalseNull=null;letfalseNaN=0/0;lettrueNum=1;lettrueStr="Where";lettrueObj={name:"Where"};lettrueArr=["前端","后端"];console.log("falseNum",!!falseNum);//falseconsole.log("falseStr",!!falseStr);//falseconsole.log("falseUndefined",!!falseUndefined);//falseconsole.log("falseNaN",!!falseNaN);//falseconsole.log("trueNum",!!trueNum);//trueconsole.log("trueStr",!!trueStr);//trueconsole.log("trueObj",!!trueObj);//trueconsole.log("trueArr",!!trueArr);//true交换对象键值letobj={key1:"value1",key2:"value2"};letrevert={};Object.entries(obj).forEach(([key,value])=>revert[value]=key);console.log(revert);数组去重值类型数组letarrNum=[1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0];letarrString=["1","2","3","4","5","6"t;,"7","8","9","0","1","2","3","4","5","6","7","8""9","0"];letarrMixed=[1,"1","2",true,false,false,1,2,"2"];arrNum=Array.from(newSet(arrNum));arrString=[...newSet(arrString)];arrMixed=[...newSet(arrMixed)];console.log(arrNum);//[1,2,3,4,5,6,7,8,9,0]console.log(arrString);//["1","2","3","4","5","6","7","8","9","0"]console.log(arrMixed);//[1,"1","2",true,false,2]引用类型数组letarrObj=[{name:"Where"},{name:"王二"},{name:"何芳"},{name:"何芳"},{name:"何芳"},{name:"何芳"},{name:"王二"},{name:"王二"},{name:"王二"},{name:"王二"},];letarrObj2=[];arrObj.forEach(item=>{arrObj2.find(find=>find.name===item.name)||arrObj2.push(item)});console.log(arrObj2);
