Are the following two validation the same:
1) IsNull(Me.Colum nName) and Me.ColumnName = ""
2) Me.ColumnName """
It would seem to be better to use: Me.ColumnName """
7  63087 
On Feb 23, 3:06 pm, "tomleb...@msn. com" <tomleb...@msn. comwrote:
Are the following two validation the same:
1) IsNull(Me.Colum nName) and Me.ColumnName = ""
2) Me.ColumnName """
It would seem to be better to use: Me.ColumnName """
No they are not. One tests for a value (empty strings are values) and
the other sees what of two values is logically greater.
An empty string is less than a 'normal' string and a numeric variable
with no value defaults to 0.
However when doing this and one of the values is Null (mainly when
using variants) the comparison will always fail because a null has no
value to test.
I find the easiest test when you need to know if something is null is
to use the Nz function. If it is, this function lets you force a
different value so that your comparison don't fail.
On Feb 23, 2:23 pm, "storrboy" <storr...@sympa tico.cawrote:
On Feb 23, 3:06 pm, "tomleb...@msn. com" <tomleb...@msn. comwrote:
Are the following two validation the same:
1) IsNull(Me.Colum nName) and Me.ColumnName = ""
2) Me.ColumnName """
It would seem to be better to use: Me.ColumnName """
No they are not. One tests for a value (empty strings are values) and
the other sees what of two values is logically greater.
An empty string is less than a 'normal' string and a numeric variable
with no value defaults to 0.
However when doing this and one of the values is Null (mainly when
using variants) the comparison will always fail because a null has no
value to test.
I find the easiest test when you need to know if something is null is
to use the Nz function. If it is, this function lets you force a
different value so that your comparison don't fail.
What is the recommended syntax to verify if a text box is empty?
I assume you should check for both nulls and empty string.
Does Me.Column "" check for both nulls and empty string?
If Nz(Me!txBoxName ,True) Then
or
If Nz(Me!txBoxName ,"") = "" then ....
or
variable = Nz(Me!txBoxName ,"")
The last argument is what to return if the value is null. Otherwise
the actual value is returned.
On 23 Feb 2007 12:31:53 -0800, "to*******@msn. com" <to*******@msn. comwrote:
>On Feb 23, 2:23 pm, "storrboy" <storr...@sympa tico.cawrote:
>On Feb 23, 3:06 pm, "tomleb...@msn. com" <tomleb...@msn. comwrote:
Are the following two validation the same:
1) IsNull(Me.Colum nName) and Me.ColumnName = ""
2) Me.ColumnName """
It would seem to be better to use: Me.ColumnName """
No they are not. One tests for a value (empty strings are values) and
the other sees what of two values is logically greater.
An empty string is less than a 'normal' string and a numeric variable
with no value defaults to 0.
However when doing this and one of the values is Null (mainly when
using variants) the comparison will always fail because a null has no
value to test.
I find the easiest test when you need to know if something is null is
to use the Nz function. If it is, this function lets you force a
different value so that your comparison don't fail.
What is the recommended syntax to verify if a text box is empty?
I assume you should check for both nulls and empty string.
Does Me.Column "" check for both nulls and empty string?
If Len(Me.MyTextBo x & "") 0 Then ...
This will catch both Nulls and ZeroLengthStrin gs in one check.
Wayne Gillespie
Gosford NSW Australia
I use the following code to check for null and empty string:
If Len(Nz(Me!txBox Name,"")) = 0 Then
PrettyCool Wayne!
I hadn't seen that one yet. All with one function
On 23 Feb 2007 16:42:13 -0800, "Ap******@gmail .com" <Ap******@gmail .comwrote:
>PrettyCool Wayne!
I hadn't seen that one yet. All with one function
I think I got it from Lyle from memory.
Wayne Gillespie
Gosford NSW Australia This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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