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When there is a situation where we need to remove items from DOM’s through JavaScript, we cannot do so directly from FileList object. We need to assign the following to an array:$('input:file#upload')[1].filesAfter that remove items from this array using splice or method of our choice and use that array.Another way is to upload files with the help of HTML file uploader and then delete corresponding objects by using JavaScript.
An assertion is a sanity-check that you can turn on or turn off when you are done with your testing of the program.The easiest way to think of an assertion is to liken it to a raise-if statement (or to be more accurate, a raise-if-not statement). An expression is tested, and if the result comes up false, an exception is raised.Assertions are carried out by the assert statement, the newest keyword to Python, introduced in version 1.5.Programmers often place assertions at the start of a function to check for valid input, and after a function call to check for valid ... Read More
Even if removing the color by code:mycanvas.clearColor(d[1],d[2],d[3],2.0); mycanvas.clear(can.COLOR_BUFFER_BIT );The screen gets cleared at beginning of next draw cycle.To create WebGLRenderingContext, previous drawing buffer can be preserved.gl = someCanvas.getContext("webgl", { preserveDrawingBuffer: true }); The default is preserveDrawingBuffer: false by making this property true, previous drawing can be easily preserved
If an audio file is stored in database and then we want to use this file as a blob or binary in an application where audio source is according to session then binary data is returned through ${sessionScope.user.music}. To load the audio file in an audio tag, data:audio/mp3;base64 works well.As for the image, image tag is used as follows:
It is because there is no dragover event handler; however, default event handler of dragover event is used. After that, no drop event is triggered.e.preventdefault is needed for dragover event before drop event.If you want to allow a drop, then default handler is prevented for canceling the event. This can be done either by returning false from an attribute-defined event listener or by calling events event.prevent default method. False is returned when the division has dragover as property.The default is prevented.
In this case, the output of CHAR_LENGTH() function depends on the condition that whether we are providing NULL as a string or we are providing simply NULL to it. Following example will demonstrate the difference −mysql> Select CHAR_LENGTH(NULL); +-------------------+ | CHAR_LENGTH(NULL) | +-------------------+ | NULL | +-------------------+ 1 row in set (0.00 sec) mysql> Select CHAR_LENGTH('NULL'); +---------------------+ | CHAR_LENGTH('NULL') | +---------------------+ | 4 | +---------------------+ 1 row in set (0.00 sec)As we can observe from the above result set that when we will provide ... Read More
In this case, the output of ASCII() function depends on the condition that whether we are providing NULL as a string or we are providing simply NULL to it. Following example will demonstrate the difference −mysql> SELECT ASCII(null); +-------------+ | ASCII(null) | +-------------+ | NULL | +-------------+ 1 row in set (0.00 sec) mysql> SELECT ASCII('null'); +---------------+ | ASCII('null') | +---------------+ | 110 | +---------------+ 1 row in set (0.00 sec) mysql> Select ASCII(NULL); +-------------+ | ASCII(NULL) | +-------------+ | NULL | +-------------+ 1 row in set ... Read More
While using the ASCII() function with WHERE clause, the output returns by it will depend upon the condition given in WHERE clause. For example, suppose we have a table named ‘Student’ and we want to get the number code, higher than 65, of the first characters of the names of the students. The query for this can be written as follows −mysql> Select * from student; +------+---------+---------+-----------+ | Id | Name | Address | Subject | +------+---------+---------+-----------+ | 1 | Gaurav | Delhi | Computers | | 2 | Aarav | Mumbai | ... Read More
When CHAR_LENGTH() or CHARACTER_LENGTH() string function is used with WHERE clause, the output returns by it will depend upon the condition given in WHERE clause. For example, suppose we have a table named ‘Student’ and we want to get only those names having number of characters less than 6, then we can write following query −mysql> Select * from Student; +------+---------+---------+-----------+ | Id | Name | Address | Subject | +------+---------+---------+-----------+ | 1 | Gaurav | Delhi | Computers | | 2 | Aarav | Mumbai | History | | 15 ... Read More
It can be understood with the help of following example in which we are using the following data from the table named ‘detail_bday’ −mysql> Select * from detail_bday; +----+---------+------------+ | Sr | Name | Birth_Date | +----+---------+------------+ | 1 | Saurabh | 1990-05-12 | | 2 | Raman | 1993-06-11 | | 3 | Gaurav | 1984-01-17 | | 4 | Rahul | 1993-06-11 | +----+---------+------------+ 4 rows in set (0.00 sec)Now, in the following two ways we can search records using the date −mysql> Select * from detail_bday Where Birth_Date = '1993-06-11'; +----+-------+------------+ | Sr | ... Read More