1:js lesson:
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Title</title> 6 7 <!-- <script src="tests.js"></script>--> 8 </head> 9 <body> 10 11 12 13 14 15 <script> 16 // <!-- alert(123)--> 17 // var x; 18 // x=12; 19 20 // var y=22; 21 // alert(x) 22 // console.log(x); 23 // console.log(y); 24 25 /*var name='liukeyu',age=28; 26 myFirstName="liu"; 27 MyFirstName="liu" 28 // 1 present int,s present string 29 var 1MyTestValue=0,sMySecondValue='hi';*/ 30 31 // function f() { 32 // 33 // } 34 35 console.log(true+1) 36 console.log(false+1) 37 // if([1,2,3]){ 38 // alert(111) 39 // } 40 // else{ 41 // alert(222) 42 // } 43 // if(null){ 44 // alert(111) 45 // } 46 // else{ 47 // alert(222) 48 // } 49 // #########################Undefined:undefined 50 var x; 51 console.log(x); 52 53 function f() { 54 document.write("<h1>hello yuan<h1>") 55 } 56 // f() 57 console.log(f()); 58 console.log(typeof f()); 59 60 // ########################Null:null for the object: 61 // var perdon=new Person(); 62 // var person=null 63 64 //NAN:not a number:belonging to Number: 65 console.log("hello"+2+true); 66 console.log(parseInt(3.123));//3 67 console.log(parseFloat('3'));//3 68 console.log(parseInt("123abc"));//123 69 console.log(parseInt("hello"));//NAN 70 console.log(parseInt("abc1234"));//NAN 71 console.log(parseInt(eval("1+1"))) 72 73 // typeof:distinguish the basic types: 74 console.log(typeof 123); 75 console.log(typeof "hello"); 76 console.log(typeof true); 77 console.log(typeof null);//object 78 console.log(typeof undefined); 79 80 console.log(typeof [12,33,44]);//object 81 console.log(typeof {"name":'yuan'});//object 82 83 //++i --i i++ i-- 84 var i=10; 85 console.log(i++);//10 86 console.log(++i);//12 87 console.log(i--);//12 88 console.log(--i);//10 89 90 //&& || ! 91 console.log("hello"&&4)//4 92 </script> 93 </body> 94 95 </html>
2:JS contrlo sentance:
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Title</title> 6 </head> 7 <body> 8 9 <p>hello liu</p> 10 <p>hello zita</p> 11 <p>hello chen</p> 12 <div>divdivdivdivdiv</div> 13 <script> 14 //if else 15 // var name="alex"; 16 // if (name=="liu"){ 17 // alert(666); 18 // } 19 // else if(name=="chen"){ 20 // alert(777); 21 // } 22 // else{ 23 // alert(888); 24 // } 25 26 //switch; 27 // var week=1; 28 // switch (week) { 29 // case 1:alert("星期一");break; 30 // case 2:alert("星期2");break; 31 // case 3:alert("星期3");break; 32 // case 4:alert("星期4");break; 33 // case 5:alert("星期5");break; 34 // case 6:alert("星期6");break; 35 // case 7:alert("星期7");break; 36 // default:alert("nothing"); 37 // } 38 39 //for&while ciruclation: 40 // for(var i=0;i<10;i++) { 41 // document.write("welcome"+i+"<br>") 42 // } 43 44 // var attr=[11,22,33]; 45 // for(var i=0;i<attr.length;i++){ 46 // document.write(i); 47 // document.write(attr[i]+"<br>") 48 // } 49 // 50 // for (i in attr){ 51 // document.write(i); 52 // document.write(attr[i]+"<br>") 53 // } 54 55 // var else_p=document.getElementsByTagName('p') 56 // console.log(else_p) 57 // // for(i in else_p){ 58 // // console.log(i) 59 // // } 60 // 61 // for (var i=0;i<else_p.length;i++){ 62 // console.log(i); 63 // console.log(else_p[i]) 64 // } 65 66 //while: 67 // var i=1,sum=0; 68 // while (i<101) { 69 // sum += i; 70 // i++; 71 // } 72 // console.log(sum) 73 74 //unnormal: 75 76 // try{ 77 // console.log(123); 78 // throw Error("define error") 79 // } 80 // catch(e){ 81 // console.log(e) 82 // } 83 // finally { 84 // console.log("finally") 85 // } 86 87 </script> 88 </body> 89 </html>
3:JS_object:
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Title</title> 6 </head> 7 <body> 8 <script> 9 //two methods of creating a string object 10 var str1="hello"; 11 // var str2=new String("hello2"); 12 // console.log(typeof str1);//string 13 // console.log(typeof str2);//object 14 15 //attribute of string 16 // console.log(str1.length); 17 18 //method of string 19 //range method 20 // console.log(str1.italics());//<i>hello</i> 21 // console.log(str1.bold()); 22 // console.log(str1.anchor()); 23 24 //x.charAt(index) 25 // var str='welcome to the world of JS' 26 // var str3=str.indexOf('l'); 27 // var str4=str.lastIndexOf('l') 28 // alert(str3);//2 29 // alert(str4);//18 30 31 // console.log(str1.substr(1,3));//ell 32 // console.log(str1.substring(1,3));//el 33 34 // console.log(str1.slice(1,4)); 35 36 //replace,split,concat 37 //-----------------------------------------------Array: 38 //create aarray 39 arr1=[1,'hello',[11,22],{'name':'liu'}]; 40 // arr2=new Array(4); 41 // arr3=new Array(1,'world',true,[1,2,3]); 42 // console.log(typeof arr1);//object 43 // console.log(typeof arr2);//object 44 // console.log(typeof arr3);//object 45 // 46 // var arr4=new Array(10);//it will regard the 10 is the size of the array; 47 // 48 //two dimension array: 49 // var week=new Array(7); 50 // for (var i=0;i<=6;i++){ 51 // week[i]=new Array(2); 52 // } 53 // week[0][0]='xingqitian'; 54 // week[0][1]='sunday' 55 // ...... 56 57 // console.log(arr1.length); 58 //join: 59 // var arr5=[1,2,3,4,'234']; 60 // console.log(arr5.join('**'));//1**2**3**4**234,when python just for the string type; 61 //Tostring: 62 // ret2 = arr1.toString(); 63 // console.log(typeof ret2);//string 64 // console.log(ret2)//1,hello,11,22,[object Object] 65 //concat 66 // var arr5=[1,2,3]; 67 // var ret3=arr5.concat([5,66]); 68 // console.log(ret3);//(5) [1, 2, 3, 5, 66] 69 // console.log(typeof ret3);//object 70 // 71 //reverse 72 // var arr6=[22,33,100,44]; 73 // console.log(arr6.reverse());//(4) [44,100, 33, 22] 74 // console.log(arr6.sort());//(4) [100, 22, 33, 44],base on the first bite 75 // function f(a,b) { 76 // if(a>b){ 77 // return 1 78 // } 79 // else if(a<b){ 80 // return -1 81 // } 82 // else{ 83 // return 0 84 // } 85 // } 86 // console.log(arr6.sort(f))//(4) [22, 33, 44, 100] 87 // function f2(a,b) { 88 // return a-b 89 // } 90 // console.log(arr6.sort(f2));//(4) [22, 33, 44, 100] 91 //slice 92 //x.splice(start,deleteCount,value,value ...)//delete and insert 93 94 //push pop:栈操作 95 // var arr7=[1,2,3]; 96 // arr7.push([7,8,9]); 97 // console.log(arr7);//(4) [1, 2, 3, Array(3)] 98 // console.log(arr7.length)//4 99 // arr7.push('hello',5); 100 // console.log(arr7);//(6) [1, 2, 3, Array(3), "hello", 5] 101 // console.log(arr7.length)//6 102 // 103 // console.log(arr7.pop());//5 104 // console.log(arr7.length)//5 105 106 //shift unshift:栈操作 107 // var arr8=[4,5,6]; 108 // arr8.unshift([11,22,33]); 109 // console.log(arr8);//(4) [Array(3), 4, 5, 6] 110 // console.log(arr8.length);//4 111 // arr8.shift(); 112 // console.log(arr8);//(3) [4, 5, 6] 113 // console.log(arr8.length);//3 114 115 //-------------------------------------------------function: 116 //method 1: 117 // function f(x,y){ 118 // alert(123); 119 // return x+y 120 // } 121 // console.log(f(32,566)); 122 // console.log(f.length) //2 123 //面试题 124 // function f(x,y) { 125 // return x+y 126 // } 127 // var f=1; 128 // var b=2; 129 // console.log(f(f,b))//js_object.html?_ijt=g5g8sb82u0gca2lqc7rc13rfv7:129 Uncaught TypeError: f is not a function 130 131 //arguments 132 // function f(x,y){ 133 // console.log(arguments[0]); 134 // console.log(arguments[1]); 135 // console.log(arguments[2]); 136 // console.log(arguments[3]); 137 // return x+y 138 // } 139 // f(1,3,5,20); 140 141 // function ADD() { 142 // var sum=0; 143 // for(var i=0;i<arguments.length;i++){ 144 // sum+=arguments[i] 145 // } 146 // return sum; 147 // } 148 // console.log(ADD(1,22,33)) 149 150 //anonymous function: 151 // func('hello');//js_object.html?_ijt=g5g8sb82u0gca2lqc7rc13rfv7:151 Uncaught TypeError: func is not a function 152 // var func=function(arg){ 153 // alert(arg) 154 // }; 155 // func('hello')//alert 156 157 (func=function(arg){ 158 alert(arg) 159 })('YUAN') 160 </script> 161 </body> 162 </html>
