先来看看运行效果：
具体代码如下：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>www.gxlcms.com 点击切换按钮颜色</title>
</head>
<body>
<button id="btn1" onclick="btn(1)">按钮1</button>
<button id="btn2" onclick="btn(2)">按钮2</button>
<button id="btn3" onclick="btn(3)">按钮3</button>
<script>
//设置背景颜色
//如果设置参数函数会节省函数数量吧
//设置flag+参数函数
flag = "btn1";
function btn1(){
document.getElementById("btn2").style.color = "black";
document.getElementById("btn3").style.color = "black";
document.getElementById("btn1").style.color = "red";
}
function btn2(){
document.getElementById("btn1").style.color = "black";
document.getElementById("btn2").style.color = "red";
document.getElementById("btn3").style.color = "black";
}
function btn3(){
document.getElementById("btn1").style.color = "black";
document.getElementById("btn2").style.color = "black";
document.getElementById("btn3").style.color = "red";
}
function btn(num){
if(num == 1){
document.getElementById(flag).style.color = "black";
document.getElementById(flag).style.backgroundColor = "white";
document.getElementById("btn1").style.color = "red";
document.getElementById("btn1").style.backgroundColor = "blue";
flag = "btn1";
}
if(num == 2){
document.getElementById(flag).style.color = "black";
document.getElementById(flag).style.backgroundColor = "white";
document.getElementById("btn2").style.color = "red";
document.getElementById("btn2").style.backgroundColor = "blue";
flag = "btn2";
}
if(num == 3){
document.getElementById(flag).style.color = "black";
document.getElementById(flag).style.backgroundColor = "white";
document.getElementById("btn3").style.color = "red";
document.getElementById("btn3").style.backgroundColor = "blue";
flag = "btn3";
}
}
</script>
</body>
</html>