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Select all contents of textbox when it receives focus (Vanilla JS or jQuery)
What is a Vanilla JS or jQuery solution that will select all of the contents of a textbox when the textbox receives focus?
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MySQL: Set user variable from result of query
...need to move the variable assignment into the query:
SET @user := 123456;
SELECT @group := `group` FROM user WHERE user = @user;
SELECT * FROM user WHERE `group` = @group;
Test case:
CREATE TABLE user (`user` int, `group` int);
INSERT INTO user VALUES (123456, 5);
INSERT INTO user VALUES (111111...
How to create a listbox in HTML without allowing multiple selection?
...eate a simple listbox, but one of the requirements is to DISALLOW multiple selection. Most of the code for listboxes goes like this -
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Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You s...
How to convert std::string to LPCSTR?
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std::string myString("SomeValue");
LPSTR lpSTR = const_cast<char*>(myString.c_str());
myString is the input string and lpSTR is it's LPSTR equivalent.
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How do I make a placeholder for a 'select' box?
...s which is working out just fine. But I'd like to use a placeholder for my selectboxes as well. Of course I can just use this code:
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Background task, progress dialog, orientation change - is there any 100% working solution?
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Step #5: In onCreate(), if getLastNonConfigurationInstance() is not null, cast it to your AsyncTask class and call your setter to associate your new activity with the task.
Step #6: Do not refer to the activity data member from doInBackground().
If you follow the above recipe, it will all work. o...
MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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Only read selected columns
...from the data.table-package:
You can specify the desired columns with the select parameter from fread from the data.table package. You can specify the columns with a vector of column names or column numbers.
For the example dataset:
library(data.table)
dat <- fread("data.txt", select = c("Year...
String concatenation vs. string substitution in Python
...ou are profiling how. For one your concat is slow because you have two str casts in it. With strings the result is the opposite, since string concat is actually faster than all the alternatives when only three strings are concerned.
– Justus Wingert
Sep 16 '15 ...