判断优化写法

if 优化写法

//普通写法if (x === 'abc' || x === 'def' || x === 'ghi' || x ==='jkl') {//logic}//简写方法if (['abc', 'def', 'ghi', 'jkl'].includes(x)) {   //logic}

//普通写法if (x > 100) {  a = true; } else {   a= false;} // 简写方法let a = (x > 100) ? true : false;

// 普通方法if (first !== null || first !== undefined || first !== '') {    let a = true;}// 简写方法let a = first|| '';

// 普通方法let test;function checkReturn() {    if (!(test === undefined)) {        return test;    } else {      return callMe('test');    }}// 简写方法function checkReturn() {return test || callMe('test');}

// 普通方法switch (data) {  case 1:    test1();  break;   case 2:    test2();  break;   case 3:    test();  break;  // And so on...}// 简写方法var data = {  1: test1,  2: test2,  3: test};data[anything] && data[anything]();

// 普通方法if (type === 'test1') {  test1();}else if (type === 'test2') {  test2();}else if (type === 'test3') {  test3();}else if (type === 'test4') {  test4();} else {  throw new Error('Invalid value ' + type);}// 简写方法var types = {  test1: test1,  test2: test2,  test3: test3,  test4: test4};var func = types[type];(!func) && throw new Error('Invalid value ' + type); func();