javascript定義函數(聲明函數)可以有三種方法：正常方法、構造函數、函數直接量
<html>
<head>
</head>
<body>
<script type="text/javascript">
function print(msg) {
document.write(msg, "<br/>");
alert("test:" + msg);
}
var add1 = new Function('a', 'b', 'return a+b');
var result = function (x, y) { return x + y; };
var result2 = function fact(x) { if (x < 1) return 1; else return x * fact(x - 1) };
document.write('調用一般的方法：');
print("<hr/>");
print('調用構造函數方法：add1(5,6)');
print(add1(5, 6));
print("<hr/>");
print("調用函數直接量法:result(3,4)");
var re = result(3, 4);
print(re);
print("調用函數直接量法:result2(3)");
print(result2(3));
print("<hr/>");
print('函數作為資料使用');
</script>
</body>
</html>
轉載于:https://www.cnblogs.com/sandyliu1999/p/4974048.html
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