console 命令行工具 X clear

console

     var $a=10;
        var a=3.14;
        var string="sb";
        var notDefined;
        var noSpace=null;
        document.write($a+"<br/>");
        document.write(a+"<br/>");
        document.write(string+"<br/>");
        document.write(notDefined+"<br/>");
        document.write(noSpace+"<br/>");
         
        var yzq1=10;
        var yzq2=20;
        var sum=yzq1+yzq2;
        var string1="oh";
        var string2="yes";
        var string1Number1=string1+yzq1;
        var number2String2=yzq2+string2;
        document.write(sum+"<br/>");
        document.write(string1+string2+"<br/>");

        var hhh=1;
        var ttt=2;
        document.write(hhh+"<br/>");
        hhh+=ttt;
        document.write(ttt+"<br/>");
        hhh-=ttt;
        document.write(hhh+"<br/>");
        hhh*=ttt;
        document.write(hhh+"<br/>");
        hhh/=ttt;
        document.write(hhh+"<br/>");

        document.write("比较运算符<br/>");
        var xy=(1+2)>(2+3);
        document.write("(1+2)>(2+3):"+xy+"<br/>");
        var xy=(2+3)<(1+2);
        document.write("(2+3)<(1+2):"+xy+"<br/>");
        var xy=((2+2)!=4);
        document.write("((2+2)!=4):"+xy+"<br/>");
        var xy=((2+2)==4);
        document.write("((2+2)==4):"+xy+"<br/>");

        document.write("逻辑运算符<br/>");
        document.write("条件运算符<br/>");

        document.write("Number('123')：" + Number("123") + "<br/>");
        document.write("Number('3.1415')：" + Number("3.1415") + "<br/>");
        document.write("Number('hao123')：" + Number("hao123") + "<br/>");
        document.write("Number('100px')：" + Number("100px"));

        document.write("parseInt('123')：" + parseInt("123") + "<br/>");
        document.write("parseInt('3.1415')：" + parseInt("3.1415") + "<br/>");
        document.write("parseInt('hao123')：" + parseInt("hao123") + "<br/>");
        document.write("parseInt('100px')：" + parseInt("100px"));
        
        document.write("parseInt('+123')：" + parseInt("+123") + "<br/>");
        document.write("parseInt('-123')：" + parseInt("-123"));

        document.write("parseFloat('123')：" + parseFloat("123") + "<br/>");
        document.write("parseFloat('3.1415')：" + parseFloat("3.1415") + "<br/>");
        document.write("parseFloat('hao123')：" + parseFloat("hao123") + "<br/>");
        document.write("parseFloat('100px')：" + parseFloat("100px")+"<br/>");
 document.write("绿叶，给你\"初恋\"般的感觉~");

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8"/>
    <title></title>
</head>
<body>
    <script type="text/javascript">
     var $a=10;
        var a=3.14;
        var string="sb";
        var notDefined;
        var noSpace=null;
        document.write($a+"<br/>");
        document.write(a+"<br/>");
        document.write(string+"<br/>");
        document.write(notDefined+"<br/>");
        document.write(noSpace+"<br/>");
         
        var yzq1=10;
        var yzq2=20;
        var sum=yzq1+yzq2;
        var string1="oh";
        var string2="yes";
        var string1Number1=string1+yzq1;
        var number2String2=yzq2+string2;
        document.write(sum+"<br/>");
        document.write(string1+string2+"<br/>");

        var hhh=1;
        var ttt=2;
        document.write(hhh+"<br/>");
        hhh+=ttt;
        document.write(ttt+"<br/>");
        hhh-=ttt;
        document.write(hhh+"<br/>");
        hhh*=ttt;
        document.write(hhh+"<br/>");
        hhh/=ttt;
        document.write(hhh+"<br/>");
    </script>
    <button onclick="alert("Welcome1")>点击1</button>
    <button onclick="callAlert()">点击2</button>
</body>
</html>