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

Variable Scope Workbench Page

JavaScript Bible, Fourth Edition
by Danny Goodman 

John Wiley & Sons CopyRight 2001

<TITLE>Variable Scope Trials</TITLE>
var headGlobal = "Gumby"
function doNothing() {
    var headLocal = "Pokey"
    return headLocal
// 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("global version of hisDog is intact: " + hisDog)


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