Checking white space properties

[vsamadi]

How to check if a text field is not empty or white space string?
I'm using condition

Code: Select all

NOT DATABASE_PROP

to check if it is not empty.
But I don't know which condition must be used for checking white space strings.

[Catalin]

Hello,

In order to achieve that, you can use a condition as it follows:

Code: Select all

(NOT DATABASE_PROP) AND (DATABASE_PROP = " ")

The above condition is equivalent to:

- the property exists and its' value is " " (an empty space)

However, if you want to check if there are multiple whitespace characters in a string (stored in a property), you might need to use a custom action for that.

For instance, a way of achieving the above is through a PowerShell script. The script may look something as it follows:

Code: Select all

// get the value of the DATABASE_PROP property in a variable
$property = AI_GetMsiProperty DATABASE_PROP

// check if the variable contains spaces
if (($property -match " ") -eq $true)
{
// set a property if the variable contains spaces. This property can further be used to form a condition.
AI_SetMsiProperty CONTAINS_SPACES true
}

For more information about the above script, please have a look over the following articles:

How to set an installer property using custom actions

PowerShell Inline Script Custom Action

Hope this helps!

Best regards,
Catalin