JavaScript DHTML/Language Basics/Random
A Random Ad Display Page
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<HTML> <HEAD> <TITLE>Displaying Random Ads</TITLE> <SCRIPT LANGUAGE="JavaScript"></SCRIPT> </HEAD> <BODY> <SCRIPT LANGUAGE="JavaScript"></SCRIPT>
Displaying Random Ads
</body> </HTML>
</source>
Find the random number in a range
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<html> <head> <title>Random Quote</title> <script type="text/javascript"> function getQuote() {
do { iValue = Math.random(); document.write(iValue+"
"); iValue *= 10; document.write(iValue+"
"); iValue = Math.floor(iValue); document.write(iValue+"
"); } while (iValue > 4) document.write(iValue);
} getQuote(); </script> </head> <body> </body> </html>
</source>
Math Random number: a random number between 0 and 1
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<html> <body> <script type="text/javascript">
document.write(Math.random())
</script> </body> </html>
</source>
Random link
<source lang="html4strict">
<html> <body> <script type="text/javascript"> var r=Math.random() if (r>0.5){
document.write("<a href="http://www.wbex.ru">wbex</a>")
}else{
document.write("<a href="http://www.google.ca">Google!</a>")
} </script> </body> </html>
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Random number from 0 to 10: a random number from 0 to 10 using the random() and round()
<source lang="html4strict">
<html> <body> <script type="text/javascript">
no=Math.random()*10 document.write(Math.round(no))
</script> </body> </html>
</source>
Random URL
<source lang="html4strict">
<HTML> <HEAD> <SCRIPT language="JavaScript"> var rand_url= new Array() rand_url[0]="http://www.wbex.ru"; rand_url[1]="http://www.google.ru"; rand_url[2]="http://www.msn.ru"; var rand_num= Math.floor(Math.random()*2); </SCRIPT> </HEAD> <BODY> <SCRIPT language="JavaScript">
document.write("<A HREF=""+rand_url[rand_num]+"">"+rand_url[rand_num]+"</A>");
</SCRIPT> </BODY> </HTML>
</source>
Unique Random Numbers
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html> <head> <title>Unique Random Numbers</title> <style type="text/css"> .head{font-family:verdana,arial,helvetica; font-weight:bold; font-size:20pt; color:#FF9900; filter:DropShadow(color=#000000, offX=2, offY=2, positive=1); width:100%} .link{font-family:verdana,arial,helvetica; font-size:10pt; color:#000000} .link:hover{font-family:verdana,arial,helvetica; font-size:10pt; color:#FF9900} </style>
<script language="JavaScript"> // Unique Random Numbers // -Picks a number of unique random numbers from an array // (c) 2002 Premshree Pillai // http://www.qiksearch.ru // http://premshree.resource-locator.ru // E-mail : qiksearch@rediffmail.ru function pickNums(nums, numArr) {
if(nums>numArr.length) { alert("You are trying to pick more elements from the array than it has!"); return false; } var pickArr=new Array(); var tempArr=numArr; for(var i=0; i<nums; i++) { pickArr[pickArr.length]=tempArr[Math.round((tempArr.length-1)*Math.random())]; var temp=pickArr[pickArr.length-1]; for(var j=0; j<tempArr.length; j++) { if(tempArr[j]==temp) { tempArr[j]=null; var tempArr2=new Array(); for(var k=0; k<tempArr.length; k++) if(tempArr[k]!=null) tempArr2[tempArr2.length]=tempArr[k]; tempArr=tempArr2; break; } } } return pickArr;
} </script>
</head> <body bgcolor="#FFFFFF">
This JavaScript picks up a number of unique random elements from an array.
<script language="JavaScript"> /* Add elements to this array */ var myArr = new Array("1","2","3","4","5","6","7","8","9"); var outArr=pickNums(5, myArr); /* Store the output */ /* Print Output */ /* Modify this part to suit your output needs */ document.write(""); for(var i=0; i<outArr.length; i++) { document.write("" + outArr[i] + " "); } document.write(""); </script>
© 2002 <a href="http://www.qiksearch.ru" class="link">Premshree Pillai</a>. |
</body> </html>
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Unique Random Sets
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html> <head> <title>Unique Random Sets</title>
<script language="JavaScript"> // Unique Random Sets Picker // Based on : Unique Random Numbers // -http://www.qiksearch.ru/javascripts/random_numbers1.htm // -Picks a number of unique random numbers from an array // (c) 2002 Premshree Pillai // http://www.qiksearch.ru, http://javascript.qik.cjb.net // E-mail : qiksearch@rediffmail.ru function pickNums(nums, numArr, pickArr, count, doFlag, iterations) {
iterations+=1; var currNum = Math.round((numArr.length-1)*Math.random()); if(count!=0) { for(var i=0; i<pickArr.length; i++) { if(numArr[currNum]==pickArr[i]) { doFlag=true; break; } } } if(!doFlag) { pickArr[count]=numArr[currNum]; // We create the array for use later count+=1; } if(iterations<(numArr.length*3)) // Compare for max iterations you want { if((count<nums)) { pickNums(nums, numArr, pickArr, count, doFlag, iterations); } } else { location.reload(); }
} </script>
</head> <body bgcolor="#FFFFFF">
This JavaScript, based on <a href="http://www.qiksearch.ru/javascripts/urn20.htm">Unique Random Numbers II</a>, picks Unique Random Sets.
© 2002 <a href="http://www.qiksearch.ru" title="Click here to visit Qiksearch.ru">Premshree Pillai</a>. |
</body> </html>
</source>