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How to check if a string starts with a specified string? [duplicate]
I'm trying to check if a string starts with http . How can I do this check?
6 Answers
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Bash if statement with multiple conditions throws an error
...ion. So your script would be like this:
my_error_flag=1
my_error_flag_o=1
if [ $my_error_flag -eq 1 ] || [ $my_error_flag_o -eq 2 ] || ([ $my_error_flag -eq 1 ] && [ $my_error_flag_o -eq 2 ]); then
echo "$my_error_flag"
else
echo "no flag"
fi
Although in your case you can disca...
Test if a variable is set in bash when using “set -o nounset”
...
#!/bin/bash
set -o nounset
VALUE=${WHATEVER:-}
if [ ! -z ${VALUE} ];
then echo "yo"
fi
echo "whatever"
In this case, VALUE ends up being an empty string if WHATEVER is not set. We're using the {parameter:-word} expansion, which you can look up in man bash under "Param...
Is there a “not in” operator in JavaScript for checking object properties?
Is there any sort of "not in" operator in JavaScript to check if a property does not exist in an object? I couldn’t find anything about this around Google or Stack Overflow. Here’s a small snippet of code I’m working on where I need this kind of functionality:
...
What is the difference between String.slice and String.substring?
Does anyone know what the difference is between these two methods?
8 Answers
8
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How to get hex color value rather than RGB value?
...could use Number.toString(16) - at least for each hex digit (or pad with 0 if under 16)
– orip
Nov 16 '09 at 8:09
19
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How to detect if my shell script is running through a pipe?
How do I detect from within a shell script if its standard output is being sent to a terminal or if it's piped to another process?
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&& (AND) and || (OR) in IF statements
...
No, it will not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other way around
if (str == null || str.isEmpty()) {
com...
From ND to 1D arrays
... 3, 4, 5, 6])
Note that ravel() returns a view of a when possible. So modifying b also modifies a. ravel() returns a view when the 1D elements are contiguous in memory, but would return a copy if, for example, a were made from slicing another array using a non-unit step size (e.g. a = x[::2]).
If...
How do I do a Date comparison in Javascript? [duplicate]
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if (date1.getTime() > date2.getTime()) {
alert("The first date is after the second date!");
}
Reference to Date object
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