console 命令行工具 X clear

console

function writeDocument(variable) {
    document.write(variable + "<br/>");
} 

var welcomeString="Welcome";

document.write(welcomeString+'<br/>');

document.write(welcomeString.length+'<br/>');

writeDocument("---------------------------------------------------");
//截取字符串
document.write(welcomeString.toLocaleLowerCase()+'<br/>');
document.write(welcomeString.toUpperCase()+'<br/>');
writeDocument(welcomeString.charAt(2));
writeDocument(welcomeString.charAt(6));
writeDocument(welcomeString.substring(3));
writeDocument(welcomeString.substring(0,2));

writeDocument("---------------------------------------------------");
//替换字符串
var sentence="We have fun in our class. Do you have fun in your class?"
writeDocument(sentence);
writeDocument(sentence.replace("class","programing class"));
writeDocument(sentence.replace(/class/g,"programing class"));

writeDocument("---------------------------------------------------");
//分割字符串
var splitSentence="We have fun in our class";
writeDocument(splitSentence);
writeDocument(splitSentence.split(" "));
writeDocument(welcomeString);
writeDocument(welcomeString.split(""));
writeDocument(sentence.split(""));

writeDocument("---------------------------------------------------");
//检索字符串位置
writeDocument(sentence.indexOf("class"));
writeDocument(sentence.lastIndexOf("class"));
writeDocument(sentence.match("class"));
writeDocument(sentence.match(/class/g));
writeDocument(sentence.search(/class/g));

writeDocument("---------------------------------------------------");
//统计字符个数
function countChar(stringValue,char){
    var count=0;
    for(var i=0;i<sentence.length;i++){
        var char=sentence.charAt(i);
                if(char.toLowerCase()=="o"){
            count+=1;
        }
    }
    return count;
}
writeDocument("字符串中含有"+countChar()+"个字母o");

writeDocument("---------------------------------------------------");
//统计字符串中数字的个数
function getNum(str){
    var num=0;
    for(var i=0;i<str.length;i++){
        var char=str.charAt(i);
        //空格转为0
        if(char!=" "&&!isNaN(char)){
            num++;
        }
    }
    return num;
}
document.write("字符串2t3hey46中有"+getNum("2t3hey46")+"个数字");

<!DOCTYPE html> 
<html>
<head>
    <meta charset="utf-8" />
    <title></title>
    <script>
    </script>
</head>
<body>
</body>
</html>