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How do I check for a network connection?
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You can check for a network connection in .NET 2.0 using GetIsNetworkAvailable():
System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable()
To monitor changes in IP address or changes in network availability use the events from the NetworkChange class:
Syst...
How to implement Rate It feature in Android App
... SharedPreferences prefs = mContext.getSharedPreferences("apprater", 0);
if (prefs.getBoolean("dontshowagain", false)) { return ; }
SharedPreferences.Editor editor = prefs.edit();
// Increment launch counter
long launch_count = prefs.getLong("launch_count", 0)...
How to read data from a zip file without having to unzip the entire file
...n zip)
{
if (header)
{
System.Console.WriteLine("Zipfile: {0}", zip.Name);
if ((zip.Comment != null) && (zip.Comment != ""))
System.Console.WriteLine("Comment: {0}", zip.Comment);
System.Console.WriteLine("\n{1,-22} {2,8} {3,5} {4,8} {5,3} {0}",
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How to specify font attributes for all elements on an html web page?
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* {
font-size: 100%;
font-family: Arial;
}
The asterisk implies all elements.
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Confusion between factor levels and factor labels
...ends?
– donodarazao
May 3 '11 at 13:02
6
I would often transform the levels right before plotting...
Check if a number has a decimal place/is a whole number
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Check variable equality against a list of values
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Extract a regular expression match
...nd adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
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Symbol for any number of any characters in regex?
...ace or any non-whitespace) as many times as possible down to and including 0.
[\s\S]*
This expression will match as few as possible, but as many as necessary for the rest of the expression.
[\s\S]*?
For example, in this regex [\s\S]*?B will match aB in aBaaaaB. But in this regex [\s\S]*B will...
Compare integer in bash, unary operator expected
... specifying a default value for $i if $i is blank, as follows:
if [ "${i:-0}" -ge 2 ] ; then ...
This will substitute the value 0 instead of $i is $i is undefined. I still maintain the quotes because, again, if $i is a bunch of blanks then it does not count as undefined, it will not be replaced ...