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Evaluate empty or null JSTL c tags
How can I validate if a String is null or empty using the c tags of JSTL ?
8 Answers
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IF… OR IF… in a windows batch file
Is there a way to write an IF OR IF conditional statement in a windows batch-file?
14 Answers
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Is there an easy way to check the .NET Framework version?
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Something like this should do it. Just grab the value from the registry
For .NET 1-4:
Framework is the highest installed version, SP is the service pack for that version.
RegistryKey installed_versions = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP");
string[] ve...
When can I use a forward declaration?
I am looking for the definition of when I am allowed to do forward declaration of a class in another class's header file:
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Does Python support short-circuiting?
Does Python support short-circuiting in boolean expressions?
3 Answers
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commandButton/commandLink/ajax action/listener method not invoked or input value not set/updated
Sometimes, when using <h:commandLink> , <h:commandButton> or <f:ajax> , the action , actionListener or listener method associated with the tag are simply not being invoked. Or, the bean properties are not updated with submitted UIInput values.
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How can I check if a string is null or empty in PowerShell?
Is there a built-in IsNullOrEmpty -like function in order to check if a string is null or empty, in PowerShell?
11 Answers...
Programmatically Lighten or Darken a hex color (or rgb, and blend colors)
Here is a function I was working on to programmatically lighten or darken a hex color by a specific amount. Just pass in a string like "3F6D2A" for the color ( col ) and a base10 integer ( amt ) for the amount to lighten or darken. To darken, pass in a negative number (i.e. -20 ).
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Does SQLAlchemy have an equivalent of Django's get_or_create?
...ject from the database if it already exists (based on provided parameters) or create it if it does not.
9 Answers
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PHP parse/syntax errors; and how to solve them
Everyone runs into syntax errors. Even experienced programmers make typos. For newcomers, it's just part of the learning process. However, it's often easy to interpret error messages such as:
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