javascript学习随记

Javascript中，也有对字符串操作的类似的方法（.substring()，.indexOf()，.length）。但在Javascript中，求字符串(str)的长度是str.length，而不是str.length()

<script>
function IndexDemo(str2){
   var str1 = "我"
   var s = str1.length;
   return(s);
}

alert(IndexDemo ("OBU"));
</script>

<script type="text/javascript" language="javascript">
String.prototype.getRealLength = function(){
   return this.replace(/[\u4E00-\u9FA5]+/g, 'aa').length;
}
alert('aa'.getRealLength());
alert('我'.getRealLength());
alert('我a'.getRealLength());
</script>

 动态改变文档标题

<title>yongfa365</title>
<script>document.title="http://hi.baidu.com/"+document.title</script>

<a href="photos/003/490.jpg" target="_blank"><img border="0" src="photos/003/490.jpg" alt="点击看全尺寸图片" onload="javascript:if(this.width>700)this.width=700"></a>

<script langage=javascript>
//鼠标滚轮控制图片大小
function bbimg(o)
{
   var zoom=parseInt(o.style.zoom, 10)||100;zoom+=event.wheelDelta/12;if (zoom>0) o.style.zoom=zoom+'%';
   return false;
}
</script>
<img src="http://hiphotos.baidu.com/yongfa365/pic/item/1ecc6a60b7052844eaf8f844.jpg" onmousewheel="return bbimg(this)"></img>

<script>
//点击放大，再点缩小，小图不变
function zoom(it){
if(it.height>300||it.width>300)it.style.zoom=300/(it.height>it.width?it.height:it.width);
}
</script>
<img onload="zoom(this);" src="http://hiphotos.baidu.com/yongfa365/pic/item/1ecc6a60b7052844eaf8f844.jpg" onclick="this.style.zoom==1?zoom(this):this.style.zoom=1" /><br />
<img onload="zoom(this);" src="http://hiphotos.baidu.com/yongfa365/pic/item/325c4bed89de01d4b21cb1f3.jpg" onclick="this.style.zoom==1?zoom(this):this.style.zoom=1" />

<script>
function a()
{
//字符组合
var s="username,password,age,sex,shengri,";
var re=/,/;
var xxx="";
s1=s.split(re);
for (i=0;i<s1.length;i++)
xxx=xxx+"\n"+"rs(\""+s1[i]+"\")=trim(\""+s1[i]+"\")";
event.srcElement.value=xxx;
}
</script>

<textarea name="baidu"  rows=10 cols=50 onclick="a()"></textarea>

<script>
function CreateColor(r)
{
//字符组合,生成可接收返回值的下拉列表，原创
var s="#000000|#F0F8FF|#FAEBD7|#00FFFF|#7FFFD4|#F0FFFF|#F5F5DC|#FFE4C4|#FFEBCD|#0000FF|#8A2BE2|#A52A2A|#DEB887|#5F9EA0|#7FFF00|#D2691E|#FF7F50|#6495ED|#FFF8DC|#DC143C|#00FFFF|#00008B|#008B8B|#B8860B|#A9A9A9|#006400|#BDB76B|#8B008B|#556B2F|#FF8C00|#9932CC|#8B0000|#E9967A|#8FBC8F|#483D8B|#2F4F4F|#00CED1|#9400D3|#FF1493|#00BFFF|#696969|#1E90FF|#B22222|#FFFAF0|#228B22|#FF00FF|#DCDCDC|#F8F8FF|#FFD700|#DAA520|#808080|#008000|#ADFF2F|#F0FFF0|#FF69B4|#CD5C5C|#4B0082|#FFFFF0|#F0E68C|#E6E6FA|#FFF0F5|#7CFC00|#FFFACD|#ADD8E6|#F08080|#E0FFFF|#FAFAD2|#90EE90|#D3D3D3|#FFB6C1|#FFA07A|#20B2AA|#87CEFA|#778899|#B0C4DE|#FFFFE0|#00FF00|#32CD32|#FAF0E6|#FF00FF|#800000|#66CDAA|#0000CD|#BA55D3|#9370DB|#3CB371|#7B68EE|#00FA9A|#48D1CC|#C71585|#191970|#F5FFFA|#FFE4E1|#FFE4B5|#FFDEAD|#000080|#FDF5E6|#808000|#6B8E23|#FFA500|#FF4500|#DA70D6|#EEE8AA|#98FB98|#AFEEEE|#DB7093|#FFEFD5|#FFDAB9|#CD853F|#FFC0CB|#DDA0DD|#B0E0E6|#800080|#FF0000|#BC8F8F|#4169E1|#8B4513|#FA8072|#F4A460|#2E8B57|#FFF5EE|#A0522D|#C0C0C0|#87CEEB|#6A5ACD|#708090|#FFFAFA|#00FF7F|#4682B4|#D2B48C|#008080|#D8BFD8|#FF6347|#40E0D0|#EE82EE|#F5DEB3|#FFFFFF|#F5F5F5|#FFFF00|#9ACD32";
var re=/\|/;
var n="";
s1=s.split(re);
for (i=0;i<s1.length;i++)
{
 n+="<option style=\"background-color:"+s1[i]+";color:"+s1[i]+"\" value=\""+s1[i]+"\"";
 if (r==s1[i])
  n+=" selected >";
 else
  n+=">";
 n+=s1[i]+"</option>";
}
document.write(n);
}
</script>

<select>
<script>CreateColor()</script>
</select>
<select>
<script>CreateColor("#D2691E")</script>
</select>
<select>
<script>CreateColor("#C71585")</script>
</select>

 光标是停在文本框文字的最后
  <script>
  function cc()
  {
  var e = event.srcElement;
  var r =e.createTextRange();
  r.moveStart('character',e.value.length);
  r.collapse(true);
  r.select();
  }
  </script>
    <input type=text name=text1 value="123" onfocus="cc()">
      <input type=text name=text1 value="123" onfocus="cc()">
        <input type=text name=text1 value="123" onfocus="cc()">
          <input type=text name=text1 value="123" onfocus="cc()">
  <input type=text name=text1 value="123" onfocus="cc()">

一个按钮  一个下拉列表         
   页面默认状态下 下拉列表为隐藏    当我点击按钮弹出列表   当我选择完列表值后自动隐藏
  当我再点击按钮是列表再次显示   

<input type=button value="go" onclick="sel.style.visibility='visible';">
<select id="sel" style="visibility:hidden" onchange="this.style.visibility='hidden';">
<option>1</option>
<option>2</option>
<option>3</option>
</select>