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Methods inside enum in C#
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281
You can write extension methods for enum types:
enum Stuff
{
Thing1,
Thing2
}
static c...
Django CharField vs TextField
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answered Sep 8 '11 at 21:23
Cat Plus PlusCat Plus Plus
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ADO.NET DataRow - check for column existence
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212
You can simply check like this:
return row.Table.Columns.Contains(columnName);
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What is the purpose of “!” and “?” at the end of method names?
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161
It's "just sugarcoating" for readability, but they do have common meanings:
Methods ending i...
Calculate difference between two datetimes in MySQL
...MySQL function. For example, you can use:
SELECT TIMESTAMPDIFF(SECOND, '2012-06-06 13:13:55', '2012-06-06 15:20:18')
In your case, the third parameter of TIMSTAMPDIFF function would be the current login time (NOW()). Second parameter would be the last login time, which is already in the database....
JavaScript: empty array, [ ] evaluates to true in conditional structures. Why is this?
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109
From http://www.sitepoint.com/javascript-truthy-falsy/
The following values are always falsy:...
ggplot2 keep unused levels barplot
...lot2)
df <- data.frame(type=c("A", "A", "A", "B", "B"), group=rep("group1", 5))
df1 <- data.frame(type=c("A", "A", "A", "B", "B", "A", "A", "C", "B", "B"), group=c(rep("group1", 5),rep("group2", 5)))
df$type <- factor(df$type, levels=c("A","B", "C"))
df1$type <- factor(df1$type, levels=c...
Difference between Iterator and Listiterator?
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151
The differences are listed in the Javadoc for ListIterator
You can
iterate backwards
obtain...
How to get a URL parameter in Express?
...issue on getting the value of tagid from my URL: localhost:8888/p?tagid=1234 .
4 Answers
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Send email with PHPMailer - embed image in body
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edited Mar 29 '14 at 17:06
Mihai Iorga
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