VBScript IsEmpty Function
Complete VBScript Reference IsEmpty function returns a Boolean value indicating whether the specified variable has been initialized. If uninitialized variable returns True, otherwise False.
grammar
IsEmpty(expression)
| 参数 | 描述 |
|---|---|
| expression | 必需。一个表达式（通常是一个变量名）。 |
Examples
Examples
<script type="text/vbscript">
Dim x
document.write(IsEmpty(x) & "<br />")
x=10
document.write(IsEmpty(x) & "<br />")
x=Empty
document.write(IsEmpty(x) & "<br />")
x=Null
document.write(IsEmpty(x))
</script>
Dim x
document.write(IsEmpty(x) & "<br />")
x=10
document.write(IsEmpty(x) & "<br />")
x=Empty
document.write(IsEmpty(x) & "<br />")
x=Null
document.write(IsEmpty(x))
</script>
Examples of the above output:
True
False
True
False
False
True
False
try it"
Complete VBScript Reference