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How to check whether a string is Base64 encoded or not

... for PHP5 //where $json is some data that can be base64 encoded $json=some_data; //this will check whether data is base64 encoded or not if (base64_decode($json, true) == true) { echo "base64 encoded"; } else { echo "not base64 encoded"; } Use this for PHP7 //$strin...
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SQL - using alias in Group By

...ceptions though: MySQL and Postgres seem to have additional smartness that allows it. share | improve this answer | follow | ...
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cleanest way to skip a foreach if array is empty [duplicate]

...t need: foreach ((array) $items as $item) { print $item; } Note: to all the people complaining about typecast, please note that the OP asked cleanest way to skip a foreach if array is empty (emphasis is mine). A value of true, false, numbers or strings is not considered empty. In addition, th...
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How can I find the last element in a List?

...elp. Enumerable.Last will throw an exception if the list is empty. If you call Enumerable.LastOrDefault and pass a list of value types the default value will be returned if the list is empty. So if you get 0 back from a List<int> you won't know if the list was empty or the last value was 0. I...
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What is Scala's yield?

...I use yield instead of map? This map code is equivalent val res = args.map(_.toUpperCase) , right? – Geo Jun 27 '09 at 12:23 4 ...
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Where is the Keytool application?

...achine, you would normally find the jdk at C:\Program Files\Java\jdk1.8.0_121\bin It is used for managing keys and certificates you can sign things with, in your case, probably a jar file. If you provide more details of what you need to do, we could probably give you a more specific answer. ...
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Why does int i = 1024 * 1024 * 1024 * 1024 compile without error?

... @WouterLievens, overflow is normally an "unusual" condition, if not an outright error condition. It is a result of finite-precision math, which most people are not intuitively expecting to happen when they do math. In some cases, like -1 + 1, it's harmless;...
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Unique fields that allow nulls in Django

...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None: class FooForm(forms.ModelForm): class Meta: model = Foo def clean_bar(self): return self.cleaned_data['bar'] or None class FooAdmin(admin.ModelAdmin...
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How to access data/data folder in Android device?

...'backup my data'. The resulting 'backup.ab' file on your computer contains all application data in android backup format. Basically it's a compressed tar file. This page explains how you can use OpenSSL's zlib command to uncompress it. You can use the adb restore backup.db command to restore the b...
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Using multiple arguments for string formatting in Python (e.g., '%s … %s')

...swered Jul 18 '14 at 17:49 Lordn__nLordn__n 31411 silver badge1111 bronze badges ...