function IsNumber(Expression)
{
Expression = Expression.toLowerCase();
RefString = "0123456789.-";
if (Expression.length < 1)
return (false);
for (var i = 0; i < Expression.length; i++)
{
var ch = Expression.substr(i, 1)
var a = RefString.indexOf(ch, 0)
if (a == -1)
return (false);
}
return(true);
}
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