Variable Scope Workbench Page : Function « Language Basics « JavaScript DHTML






  1. JavaScript DHTML
  2. Language Basics
  3. Function

Variable Scope Workbench Page

   
/*
JavaScript Bible, Fourth Edition
by Danny Goodman 

John Wiley & Sons CopyRight 2001
*/

<HTML>
<HEAD>
<TITLE>Variable Scope Trials</TITLE>
<SCRIPT LANGUAGE="JavaScript">
var headGlobal = "Gumby"
function doNothing() {
    var headLocal = "Pokey"
    return headLocal
}
</SCRIPT>
</HEAD>
<BODY>
<SCRIPT LANGUAGE="JavaScript">
// two global variables
var aBoy = "Charlie Brown"
var hisDog = "Snoopy"
function testValues() {
    var hisDog = "Gromit"  // initializes local version of "hisDog"
    var page = ""
    page += "headGlobal is: " + headGlobal + "<BR>"
    // page += "headLocal is: " + headLocal + "<BR>" // : headLocal not defined
    page += "headLocal value returned from head function is: " + doNothing() + "<P>"
    page += " aBoy is: " + aBoy + "<BR>" // picks up global
    page += "local version of hisDog is: " + hisDog + "<P>" // "sees" only local
    document.write(page)
}

testValues()
document.write("global version of hisDog is intact: " + hisDog)
</SCRIPT>
</BODY>
</HTML>








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