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Which is preferred: Nullable.HasValue or Nullable != null?
... what output it produced in labels:
int? val = null;
lbl_Val.Text = val.ToString(); //Produced an empty string.
lbl_ValVal.Text = val.Value.ToString(); //Produced a runtime error. ("Nullable object must have a value.")
lbl_ValEqNull.Text = (val == null).ToString(); //Produced "True" (without the qu...
How to reduce iOS AVPlayer start delay
Note, for the below question: All assets are local on the device -- no network streaming is taking place. The videos contain audio tracks.
...
NSString: isEqual vs. isEqualToString
What is the difference between isEqual: and isEqualToString: ?
5 Answers
5
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The JPA hashCode() / equals() dilemma
...lds for business ID instead, but generally that's not the case
private String screenName;
private String email;
// I don't put UUID generation in constructor for performance reasons.
// I call setUuid() when I create a new entity
public User() {
}
// This method is onl...
What is the difference between IEqualityComparer and IEquatable?
...
A better example would be comparisons between strings. It makes sense to have a string comparison method which regards strings as equal only if they contain the same sequence of bytes, but there are other useful comparison methods which also constitute equivalence relat...
How can I check if a value is a json object?
...y server side code returns a value which is a json object on success and a string 'false' on failure. Now how can I check whether the returned value is a json object?
...
TypeError: sequence item 0: expected string, int found
...
string.join connects elements inside list of strings, not ints.
Use this generator expression instead :
values = ','.join(str(v) for v in value_list)
...
Check if Key Exists in NameValueCollection
...key is not found;
So you can just:
NameValueCollection collection = ...
string value = collection[key];
if (value == null) // key doesn't exist
2) if the specified key is found and its associated value is null.
collection[key] calls base.Get() then base.FindEntry() which internally uses ...
How to add Action Bar from support library into PreferenceActivity?
...oid:minHeight="?attr/actionBarSize"
app:navigationContentDescription="@string/abc_action_bar_up_description"
android:background="?attr/colorPrimary"
app:navigationIcon="?attr/homeAsUpIndicator"
app:title="@string/action_settings"
/>
SettingsActivity.java :
public class Settin...
SQL Data Reader - handling Null column values
...!SqlReader.IsDBNull(indexFirstName))
{
employee.FirstName = sqlreader.GetString(indexFirstName);
}
That's your only reliable way to detect and handle this situation.
I wrapped those things into extension methods and tend to return a default value if the column is indeed null:
public static str...