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Asp.net - Add blank item at top of dropdownlist
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After your databind:
drpList.Items.Insert(0, new ListItem(String.Empty, String.Empty));
drpList.SelectedIndex = 0;
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How to check if a variable exists in a FreeMarker template?
... This only check if the var exists. But if you have an empty String in "userName", the <#if userName??> will return true !! See @user1546081 answer on this page to address this issue.
– Adrien Be
Jan 15 '13 at 10:22
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What's better at freeing memory with PHP: unset() or $var = null
...red to hold whatever value it was previously holding. For example, a long string. If the string wasn't a constant and its reference count drops to zero, then that memory should be freed. Unset is cleaner - it no longer maintains a reference. You do have to wait for garbage collection, but it's s...
How can I output UTF-8 from Perl?
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FWIW here is the reason: strings that contains only latin1 (ISO-8859-1) characters, despite being stored more or less in utf8, will be output as latin1 by default. This way scripts from a pre-unicode era still work the same, even with a unicode-aware...
Check whether a cell contains a substring
...here an in-built function to check if a cell contains a given character/substring?
9 Answers
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How to get package name from anywhere?
...he main activity's onCreate() method:
Global to the class:
public static String PACKAGE_NAME;
Then..
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
PACKAGE_NAME = getApplicationContext().getPackageName(...
How do you check that a number is NaN in JavaScript?
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If you want an empty string to be interpreted as NaN, then yes. (I’m not saying you always would.)
– Paul D. Waite
Apr 16 '10 at 12:20
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How do I get the path of the assembly the code is in?
...e following property as we use this often in unit testing.
public static string AssemblyDirectory
{
get
{
string codeBase = Assembly.GetExecutingAssembly().CodeBase;
UriBuilder uri = new UriBuilder(codeBase);
string path = Uri.UnescapeDataString(uri.Path);
r...
Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
... -e $VAR ] , but it turns out that was also evaluating as true on an empty string; which I do not want.
5 Answers
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HttpServletRequest - how to obtain the referring URL?
...lable in the HTTP referer header. You can get it in a servlet as follows:
String referrer = request.getHeader("referer"); // Yes, with the legendary misspelling.
You, however, need to realize that this is a client-controlled value and can thus be spoofed to something entirely different or even re...