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How do you query for “is not null” in Mongo?
...roposition:
db.collection_name.find({"field_name":{$type:2}}) //type:2 == String
You can check on the required attribute's type, it will return all the documents that its field_name queried contains a value because you are checking on the filed's type else if it is null the type condition doesn't...
Why is the default value of the string type null instead of an empty string?
It's quite annoying to test all my strings for null before I can safely apply methods like ToUpper() , StartWith() etc...
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How to find files that match a wildcard string in Java?
This should be really simple. If I have a String like this:
16 Answers
16
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C compile error: “Variable-sized object may not be initialized”
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This gives error:
int len;
scanf("%d",&len);
char str[len]="";
This also gives error:
int len=5;
char str[len]="";
But this works fine:
int len=5;
char str[len]; //so the problem lies with assignment not declaration
You need to put value in the following way:
s...
How do I make my string comparison case insensitive?
I created a Java program to compare two strings:
12 Answers
12
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How do I work around JavaScript's parseInt octal behavior?
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@Grodriguez, and when 0 in |0 is a string?
– Oleg V. Volkov
Oct 24 '14 at 16:29
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How to capitalize the first letter of a String in Java?
I am using Java to get a String input from the user. I am trying to make the first letter of this input capitalized.
55 ...
How can I format a String number to have commas and round?
...at is the best way to format the following number that is given to me as a String?
10 Answers
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How to pass data from 2nd activity to 1st activity when pressed back? - android
...f (requestCode == 1) {
if(resultCode == RESULT_OK) {
String strEditText = data.getStringExtra("editTextValue");
}
}
}
If you can, also use SharedPreferences for sharing data between Activities.
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How to convert a color integer to a hex String in Android?
...get RRGGBB, and the %06X gives you zero-padded hex (always 6 chars long):
String hexColor = String.format("#%06X", (0xFFFFFF & intColor));
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