JavaScript 经典代码（9）

<style>
BODY {
 FONT-SIZE: 9pt;
}
TD {
 FONT-SIZE: 9pt; LINE-HEIGHT: 11pt;
}
input {
 FONT-SIZE: 9pt;
}
SELECT {
 FONT-SIZE: 9pt; TEXT-ALIGN: center; WIDTH: 100px;
}
span {
 FONT-SIZE: 12pt;
}
</style>

<script language=JavaScript>
/*
All Files are Designed & Writen by Windy_sk, you can use it freely but ...
YOU MUST KEEP THIS ITEM !
Email: <a href="mailto:windy_sk@126.com">windy_sk@126.com</a>
*/

window.onload = function(){
 var color_list = new Array();
 var hex = new Array(6);
 var CurColor;
 var CurIndex;
 hex[0] = "FF"
 hex[1] = "CC"
 hex[2] = "99"
 hex[3] = "66"
 hex[4] = "33"
 hex[5] = "00"
 for(var x=0;x<6;x++){
  for(var y=0;y<6;y++){
   for(var z=0;z<6;z++){
    CurColor = hex[x] + hex[y] + hex[z];
    CurIndex = color_start.options.length;
    color_start.options[CurIndex] = new Option("",CurColor);
    color_start.options[CurIndex].style.backgroundColor = "#"+ CurColor;
    CurIndex = color_end.options.length;
    color_end.options[CurIndex] = new Option("",CurColor);
    color_end.options[CurIndex].style.backgroundColor = CurColor;
   }
  }
 }
}

function Dec2Any(str,num){
 if(!/\d+/.test(str)) return NaN;
 if(!/\d+/.test(num)) return NaN;
 var num=eval(num);
 if(num>36 || num<2)  return NaN;
 var the_str="0123456789abcdefghijklmnopqrstuvwxyz";
 var str=eval(str);
 var residue=0;
 var result="";
 while(true){
  residue=str%num;
  result = the_str.charAt(residue) + result;
  if(str<num) break;
  str=Math.floor(str/num);
 }
 return(result);
}

function get_color(the_num){
 if(the_num > 255) the_num = 255;
 if(the_num < 0)   the_num = 0;
 var the_color = Dec2Any(the_num,16);
 if(the_color.length==1) the_color = "0" + the_color;
 return the_color;
}

function build_text(str,C_start,C_end){
 var the_len = str.length;
 var R_start = eval("0x" + C_start.substr(0,2));
 var R_end = eval("0x" + C_end.substr(0,2));
 var R_unit = Math.floor((R_start - R_end)/the_len);
 var G_start = eval("0x" + C_start.substr(2,2));
 var G_end = eval("0x" + C_end.substr(2,2));
 var G_unit = Math.floor((G_start - G_end)/the_len);
 var B_start = eval("0x" + C_start.substr(4,2));
 var B_end = eval("0x" + C_end.substr(4,2));
 var B_unit = Math.floor((B_start - B_end)/the_len);
 var CurColorStr = "";
 var ResultStr = "";
 var tmp;
 show.value  = "";
 for(var i=0;i<the_len;i++){
  CurColorStr = "#";
  CurColorStr += get_color(R_start - i * R_unit);
  CurColorStr += get_color(G_start - i * G_unit);
  CurColorStr += get_color(B_start - i * B_unit);
  ResultStr   += "<font color='"+CurColorStr+"'>"+str.substr(i,1)+"</font>";
  show.value  += "<font color='"+CurColorStr+"'>"+str.substr(i,1)+"</font>\n";
 }
 return ResultStr;
}

function BuildIt(){
 clearInterval(flash_timer);
 ShowText.innerHTML = build_text(the_text.value,color_start.value,color_end.value);
 if(flash.checked) Flash_text();
}

var flash_timer = null;
var color_list  = null;

function Flash_text(){
 var obj_list = ShowText.children;
 color_list   = new Array();
 for(var i=0;i<obj_list.length;i++){
  color_list[color_list.length] = ShowText.children[i].color;
 }
 flash_timer = setInterval("FlashIt()",50);
}

function FlashIt(){
 var tmp_arr = new Array();
 for(var i=0;i<color_list.length-1;i++){
  tmp_arr[i+1] = color_list[i];
 }
 tmp_arr[0] = color_list[i];
 color_list = tmp_arr;
 for(var i=0;i<color_list.length;i++){
  ShowText.children[i].color = color_list[i];
 }
}

</script>

<table>
  <tr>
    <td colspan=3>显示文字： <input id=the_text type=text size=50 value="彩虹文字彩虹文字彩虹文字彩虹文字彩虹文字"></td>
  </tr>
  <tr>
    <td>起始颜色： <select id="color_start" onChange="BuildIt();the_text.focus()"></select></td>
    <td> ---- </td>
    <td>结束颜色： <select id="color_end" onChange="BuildIt();the_text.focus()"></select></td>
  </tr>
  <tr>
    <td colspan=3><input id=flash type=checkbox onclick="this.checked?Flash_text():clearInterval(flash_timer)"><label for=flash>闪烁</label></td>
  </tr>
</table>
<span id=ShowText style=""></span>
<br>
<textarea id=show rows=15 cols=50></textarea>