本文实例讲述了JavaScript实现彩虹文字效果的方法。分享给大家供大家参考。具体如下：
<HTML> <HEAD> <TITLE>Rainbow Text</TITLE> <SCRIPT LANGUAGE="JavaScript"> <!-- Begin hide from old browsers function createHexArray(n) { this.length = n; for (var i = 1; i <= n; i++) this[i] = i - 1; this[11] = "A"; this[12] = "B"; this[13] = "C"; this[14] = "D"; this[15] = "E"; this[16] = "F"; return this; } hx = new createHexArray(16); function convertToHex(x) { if (x < 17) x = 16; var high = x / 16; var s = high+""; s = s.substring(0, 2); high = parseInt(s, 10); var left = hx[high + 1]; var low = x - high * 16; if (low < 1) low = 1; s = low + ""; s = s.substring(0, 2); low = parseInt(s, 10); var right = hx[low + 1]; var string = left + "" + right; return string; } function makeRainbow(text) { text = text.substring(0, text.length); color_d1 = 255; mul = color_d1 / text.length; for(var i = 0; i < text.length; i++) { color_d1 = 255*Math.sin(i / (text.length / 3)); color_h1 = convertToHex(color_d1); color_d2 = mul * i; color_h2 = convertToHex(color_d2); k = text.length; j = k - i; if (j < 0) j = 0; color_d3 = mul * j; color_h3 = convertToHex(color_d3); document.write("<FONT COLOR="#" + color_h3 + color_h1 + color_h2 + "">" + text.substring(i, i + 1) + "</FONT>"); } } // End hide from old browsers --> </script> </HEAD> <body bgcolor="#FFFFCC"> <center> <strong> <font size=6> <script> <!-- // change to your own text ... makeRainbow("Welcome to Boulder City Nevada"); document.write("<br>"); makeRainbow("The best dam city in the USA"); // --> </script> </font> </strong> </center> </body> </html>
希望本文所述对大家的javascript程序设计有所帮助。