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What's the main difference between int.Parse() and Convert.ToInt32
...u'd use Int32.Parse().
If you're collecting input from a user, you'd generally use Int32.TryParse(), since it allows you more fine-grained control over the situation when the user enters invalid input.
Convert.ToInt32() takes an object as its argument. (See Chris S's answer for how it works)
Conv...
E11000 duplicate key error index in mongodb mongoose
... null value.
In other words, a sparse index is ok with multiple documents all having null values.
sparse indexes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
Include jQuery in the JavaScript Console
...ebsite I would like to get the number of rows in a table. I know this is really easy with jQuery.
20 Answers
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Android studio: new project vs new module
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oO is a module really that much?!
– Martin Pfeffer
Oct 30 '15 at 3:41
1
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How to see which commits in one branch aren't in the other?
...rence. For example, if you have two branches, A and B, a usual way to list all commits on only one side of them is with --left-right, like the example above in the description of that option. It however shows the commits that were cherry-picked from the other branch (for example, "3rd on b" may be c...
Alarm Manager Example
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I tried the solution from XXX and while it did initially work, at some point it stopped working. The onReceive never got called again. I spent hours trying to figure out what it could be. What I came to realize is that the Intent for whatever mysterious reason was no longer be...
Bash set +x without it being printed
...ution to this just recently when I became annoyed with it:
shopt -s expand_aliases
_xtrace() {
case $1 in
on) set -x ;;
off) set +x ;;
esac
}
alias xtrace='{ _xtrace $(cat); } 2>/dev/null <<<'
This allows you to enable and disable xtrace as in the following, wh...
What is the most efficient way to concatenate N arrays?
...w array that concatenates two existing arrays, it appears concat() is generally faster. For the case of concatenating an array onto an existing array in place, push() is the way to go. I updated my answer.
– Tim Down
Apr 22 '12 at 22:12
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How to avoid java.util.ConcurrentModificationException when iterating through and removing elements
...t of values you wish to remove, adding to that list within the loop, then call originalList.removeAll(valuesToRemove) at the end
Use the remove() method on the iterator itself. Note that this means you can't use the enhanced for loop.
As an example of the second option, removing any strings with ...
How to present popover properly in iOS 8
... you talk to the view controller inside of it to set the content size, by calling the property preferredContentSize
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