1     var input=prompt("请输入 身份证号码：");
2     var char=input.charAt(input.length-2);
3     console.log(char%2==0?"女":"男");

1     var input=prompt("输入消息：");
2     var result=[];
3     for (i=0;i<input.length;i++){
4         result.push(input.charCodeAt(i));
5     };
6     document.write(result.join(""));

 1     var input=prompt("输入消息：");
 2     var result=[];
 3     for (i=0;i<input.length;i++){
 4         var num=input.charCodeAt(i)
 5         if(num<10000){
 6             var arr=[0,0,0,0,0];
 7             var code=num+"";
 8             var start=5-code.length;
 9             for(var n=0;n<code.length;n++){
10             arr[start]=code[n];
11             start++;
12             }
13             num=arr.join("")
14         }
15         result.push(num)
16     };
17     document.write(result)

1     var str='女神说要来，我草草的收拾了下房间，结果她又说不来了，我说：我草！';
2     var index=-1;
3     while((index=str.indexOf("我草",index+1))!=-1){
4         console.log("位置"+index+    "发现关键字");
5     }

1 var input=prompt("请输入 身份证号码：");
2 var char=input.charAt(input.length-2);
3 var birth=input.slice(6,6+8);
4 console.log(birth);
5 console.log(char%2==0?"女":"男");

1     var str="no zuo no die";
2     var words=str.split(" ");
3     for(var i=0;i<words.length;i++){
4         words[i]=words[i][0].toUpperCase()+words[i].substring(1);
5     };
6     str=words.join(" ");
7     document.write(str)

 1     str="选购AppleCare+,延保2年";
 2     var negCount=0;
 3     var numCount=0;
 4     var chsCount=0;
 5     var other=0;
 6     for (var i=0;i<str.length;i++){
 7         var num=str.charCodeAt(i);
 8         if(num>=19968&&num<=40869){
 9             chsCount++;
10         }else if((num>=65&&num<=90)||(num>=97&&num<=122)){
11             negCount++;
12         }else if(num>=48&&num<=57){
13             numCount++
14         }else{
15             other++;
16         }
17     }
18     document.write("<br>"+"汉字："+chsCount+
19     "<br>"+"字母："+negCount+
20     "<br>"+"数字："+numCount+
21     "<br>"+"其他字符："+other);

1     var str="No zuo no die";
2     var reg=/no/ig;
3     str=str.replace(reg,"~~");
4     console.log(str);

1     var str="No zuo no die";
2     var reg=/no/ig;
3     var kwords=str.match(reg);
4     console.log(kwords);
5     str=str.replace(reg,"~~");
6     console.log(str+"<br>");
7     if(kwords!==null){
8         document.write("共替换了"+kwords.length+"处");
9     }