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How to use FormData for AJAX file upload?
This is my HTML which I'm generating dynamically using drag and drop functionality.
9 Answers
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PG undefinedtable error relation users does not exist
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At first, you shall detach all connections out of database. By default you use the development environment. Then try to reset database with the following:
rake db:reset
The rake db:reset task will drop the database and set it up again....
Android Webview - Webpage should fit the device screen
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You have to calculate the scale that you need to use manually, rather than setting to 30.
private int getScale(){
Display display = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int width = display.getWidth();
Double val = new Double...
What, exactly, is needed for “margin: 0 auto;” to work?
...ple's heads:
The element must have a width that is not auto2
Note that all of these conditions must be true of the element being centered for it to work.
1 There is one exception to this: if your fixed or absolutely positioned element has left: 0; right: 0, it will center with auto margins.
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HashMap with multiple values under the same key
... to this approach is that you have to write a lot of boiler-plate code for all of these very simple container classes.
3. Using a tuple
// you'll have to write or download a Tuple class in Java, (.NET ships with one)
// create our map
Map<String, Tuple2<Person, Person> peopleByForename =...
Select SQL Server database size
...02.81 814.81
-- sp_spaceused
database_name database_size unallocated space
---------------- ------------------ ------------------
xxxxxxxxxxx 814.81 MB 13.04 MB
Function:
ALTER FUNCTION [dbo].[GetDBSize]
(
@db_name NVARCHAR(100)
)
RETURNS TABLE
AS
RETURN
SELE...
What's a concise way to check that environment variables are set in a Unix shell script?
...is therefore in the Korn Shell, and in the POSIX shells, including specifically Bash.
It is usually documented in the shell's man page in a section called Parameter Expansion. For example, the bash manual says:
${parameter:?word}
Display Error if Null or Unset. If parameter is null or unset, the...
Running a cron job at 2:30 AM everyday
...mmand
Crontab Format:
MIN HOUR DOM MON DOW CMD
Format Meanings and Allowed Value:
MIN Minute field 0 to 59
HOUR Hour field 0 to 23
DOM Day of Month 1-31
MON Month field 1-12
DOW Day Of Week 0-6
CMD Command Any command to be executed.
Restart cro...
What exceptions should be thrown for invalid or unexpected parameters in .NET?
...o, that do not focus so much on the argument itself, but rather judge the call as a whole:
InvalidOperationException – The argument might be OK, but not in the current state of the object. Credit goes to STW (previously Yoooder). Vote his answer up as well.
NotSupportedException – The argument...
Is std::vector copying the objects with a push_back?
...e name of an entity declared as rvalue reference, then the argument is actually an lvalue and will not be moved from) - check my edit to the answer of "Karl Nicoll" which made that mistake initially
– M.M
Apr 16 '17 at 0:17
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