JS是一种脚本语言
javascript
1.JS实现HTML输出
html
<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html" charset="utf-8"> <title> This is my HTML</title> </head> <body> <script type="text/javascript"> document.write("JS实现HTML输出"); </script> </body> </html>
2.JS实现对事件做出反应
java
<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html" charset="utf-8"> <title> This is my HTML</title> </head> <body> <button type="button" onclick="alert('点击了按钮')">按钮</button> </body> </html>
3.JS改变HTML内容
测试
<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html" charset="utf-8"> <title> This is my HTML</title> </head> <body> <p id="changeContent">本来输出的内容</p> <script type="text/javascript"> function changeHTMLContent() { //找到元素(很明显,本例子的元素是p) x=document.getElementById("changeContent"); //改变的内容 x.innerHTML="这是替换的内容"; //改变颜色 x.style.color = "#00ff00"; } </script> <button type="button" onclick="changeHTMLContent()">按钮</button> </body> </html>
4.JS验证输入
ui
<!DOCTYPE html> <html> <head> <meta http-equiv="Content-Type" content="text/html" charset="utf-8"> <title> This is my HTML</title> </head> <body> <p>验证输入的是否为数字,若是不为数字,弹出提示框提示</p> <input id="test" type="text"> <script type="text/javascript"> function check() { var x = document.getElementById("test").value; if (x == "" || isNaN(x)) { alert("请输入数字"); }; } </script> <button type="button" onclick="check()">点击测试</button> </body> </html>