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string.IsNullOrEmpty(string) vs. string.IsNullOrWhiteSpace(string)
...lOrWhiteSpace(String value) {
if (value == null) return true;
for(int i = 0; i < value.Length; i++) {
if(!Char.IsWhiteSpace(value[i])) return false;
}
return true;
}
Examples
string nullString = null;
string emptyString = "";
string whitespaceString = " ";
string n...
How to change identity column values programmatically?
...hen switch back.
Assuming the following structure
CREATE TABLE Test
(
ID INT IDENTITY(1,1) PRIMARY KEY,
X VARCHAR(10)
)
INSERT INTO Test
OUTPUT INSERTED.*
SELECT 'Foo' UNION ALL
SELECT 'Bar' UNION ALL
SELECT 'Baz'
Then you can do
/*Define table with same structure but no IDENTITY*/
CREATE TAB...
View's getWidth() and getHeight() returns 0
...ew View(this) {
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
super.onLayout(changed, l, t, r, b);
view.getHeight(); //height is ready
}
};
Also mind, that onLayout will be called many times, so be considerate what you do in the method,...
Can I replace groups in Java regex?
...nt method:
public static String replaceGroup(String regex, String source, int groupToReplace, String replacement) {
return replaceGroup(regex, source, groupToReplace, 1, replacement);
}
public static String replaceGroup(String regex, String source, int groupToReplace, int groupOccurrence, Stri...
Set focus on TextBox in WPF from view model
...perty of the control I want to shift the focus to is tied to a multi-value converter. Apparently, the GotFocus event handler gets called before the multi-value converter does...which means the control, at that point, is disabled, so as soon as GotFocus completes, LostFocus gets called (I guess becau...
Can we write our own iterator in Java?
...
Sure. An iterator is just an implementation of the java.util.Iterator interface. If you're using an existing iterable object (say, a LinkedList) from java.util, you'll need to either subclass it and override its iterator function so that you return your own, or provide a means of wrapping a sta...
What is the best way to check for Internet connectivity using .NET?
What is the fastest and most efficient way to check for Internet connectivity in .NET?
27 Answers
...
How do I automatically scroll to the bottom of a multiline text box?
I have a textbox with the .Multiline property set to true. At regular intervals, I am adding new lines of text to it. I would like the textbox to automatically scroll to the bottom-most entry (the newest one) whenever a new line is added. How do I accomplish this?
...
Java Reflection Performance
...eption
{
long start = System.currentTimeMillis();
for (int i=0; i<1000000; i++)
{
A a = new A();
a.doSomeThing();
}
System.out.println(System.currentTimeMillis() - start);
}
public static void doReflection() throws Excep...
How to make a countdown timer in Android?
... }
} catch (Exception e) {
e.printStackTrace();
}
}
};
handler.postDelayed(runnable, 0);
}
protected void onStop() {
super.onStop();
handler.removeCallbacks(runnable);
}
}
activity_...