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Best way to check if a Data Table has a null value in it
... || dr1["Columnname"].ToString() == ""
select Columnname);
Here Replace Columnname with table column name and "" your search item in above code we looking null value.
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How to add a custom button state
...tion indicated by @(Ted Hopp) works, but needs a little correction: in the selector, the item states need an "app:" prefix, otherwise the inflater won't recognise the namespace correctly, and will fail silently; at least this is what happens to me.
Allow me to report here the whole solution, with s...
LEGO EV3 机器人传感器面板 · App Inventor 2 中文网
...ListPicker1.AfterPicking 时
调用 BluetoothClient1.Connect(ListPicker1.Selection)
如果 BluetoothClient1.IsConnected 那么
设置 Clock1.TimerEnabled 为 true
设置 Screen1.Title 为 "Connected"
步骤2：传感器轮询
Clock.Timer 事件每 200ms 触发...
Why is it bad style to `rescue Exception => e` in Ruby?
...IFT-ESC), go to the "processes" tab, find your process, right click it and select "End process".
If you are working with someone else's program which is, for whatever reason, peppered with these ignore-exception blocks, then putting this at the top of the mainline is one possible cop-out:
%W/INT Q...
How to add title to subplots in Matplotlib?
...set_title can be used to set title, once the proper axes(ax) or subplot is selected.
import matplotlib.pyplot as plt
fig, ax = plt.subplots(2, 2, figsize=(6, 8))
for i in range(len(ax)):
for j in range(len(ax[i])):
## ax[i,j].imshow(test_images_gr[0].reshape(28,28))
ax[...
Does Notepad++ show all hidden characters?
...ould identify the character, where cursor takes 2 arrow keys
to move, just select that character.
do Ctrl-F
now you can count or
replace or even mark all such characters
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How to manage REST API versioning with spring?
...) endpoint from user v2!
Rest Documentation
As i said before the reason i select the URL-based versioning approach is that some tools like swagger do not document differently the endpoints with the same URL but different content type. With this solution, both endpoints are displayed since have diff...
How to simulate a higher resolution screen? [closed]
...esolution throws this: "Your Screen Resolution is too small The pop-up you selected is too big for the screen resolution you use. Your screen resolution is 1440 pixels by 900 pixels. The pop-up window you tried to open is 1920 pixels by 1200. "
– HappyDeveloper
...
How do I use a file grep comparison inside a bash if/else statement?
...m grep --help, but also see man grep:
Exit status is 0 if any line was selected, 1 otherwise;
if any error occurs and -q was not given, the exit status is 2.
if grep --quiet MYSQL_ROLE=master /etc/aws/hosts.conf; then
echo exists
else
echo not found
fi
You may want to use a more specif...
ActiveRecord: size vs count
... don't know what you are doing, use size...
count
Resolves to sending a Select count(*)... query to the DB. The way to go if you don't need the data, but just the count.
Example: count of new messages, total elements when only a page is going to be displayed, etc.
length
Loads the required dat...