Handling undefined elements in Javascript

Some times you may verify the element for null but if the element is undefined then null condition fails so best practice is to check for null and undefined.

checking for null

if(document.getElementsByName("TxtElement1")  == null)
{
alert("the element is null");
}

checking for undefined

if(document.getElementsByName("TxtElement1").value == 'undefined')
{
alert("the element is undefined");
}

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About kakani santosh kumar

Working as Software Engineer in Prithvi Information Solutions having 3 years of Experience in Dotnet Framework ranging from 1.1 to 3.5
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