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javascript - How to get a count of all checked checkboxes on a page

I want to count how many checkboxes a user has selected. For example, from a group of 10 checkboxes if he ... by that statement as well? See Question&Answers more detail:os...

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c# - Why can’t DateTime.ParseExact() parse the AM/PM in “4/4/2010 4:20:00 PM” using “M'/'d'/'yyyy H':'mm':'ss' 'tt”

I'm using c#, and if I do DateTime.ParseExact("4/4/2010 4:20:00 PM", "M'/'d'/'yyyy H':'mm':'ss' ... what am I doing wrong with using tt? Thanks! See Question&Answers more detail:os...

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c# - Performance of LINQ Any vs FirstOrDefault != null

There are multiple places in an Open Source Project (OSP) code I contribute, where it has to be determined if ... or am I missing something? See Question&Answers more detail:os...

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apache spark - Adding a group count column to a PySpark dataframe

I am coming from R and the tidyverse to PySpark due to its superior Spark handling, and I am struggling ... canonical way to accomplish this? See Question&Answers more detail:os...

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algorithm - How can I generate all permutations of an array in Perl?

What's the best (elegant, simple, efficient) way to generate all n! permutations of an array in perl? For example, if ... ) ){ print "@perm "; } See Question&Answers more detail:os...

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How to get iOS device MAC address programmatically

How do I get an iOS device's MAC code programmatically in my app? See Question&Answers more detail:os...

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c++ - std::vector iterator invalidation

There have been a few questions regarding this issue before; my understanding is that calling std::vector::erase will ... me that it's valid. See Question&Answers more detail:os...

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Multiple Counts with single query in mongodb

I am new to Mongo Db and would appreciate some help with this query. I have been sifting through posts here for the ... ": "Unreleased" } ] }) See Question&Answers more detail:os...

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events - Wait until Application.Calculate has finished

Can I force my vba script to wait until Application.Calculate has finished to recalculate all the formulas? See Question&Answers more detail:os...

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regex - javascript unicode emoji regular expressions

i want to replace all emoji in string with icon now i successfully replaced those {:) :D :P :3 <3 XP ... to change any emoji to those character See Question&Answers more detail:os...

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html - contenteditable=false inside contenteditable=true block is still editable in IE8

I have the following HTML intending to make sure that the inner span isn't editable. This works in other ... treats this properly as well? See Question&Answers more detail:os...

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c++ - Rationale of enforcing some operators to be members

There are 4 operators in C++ which can be overloaded but cannot be overloaded as freestanding (aka nonmember, ... ideas about the other three? See Question&Answers more detail:os...

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python - top values from dictionary

How do I retrive the top 3 list from a dictionary? >>> d {'a': 2, 'and': 23, 'this': 14, 'only.': ... Expected result: and: 23 only: 21 this: 14 See Question&Answers more detail:os...

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c++ - Logical AND, OR: Is left-to-right evaluation guaranteed?

Is left-to-right evaluation of logical operators (&& ||) guaranteed? Let's say I have this: SDL_Event event; if ( ... ) than if (b && a). See Question&Answers more detail:os...

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media player - How do I play an mp3 in the res/raw folder of my android app?

I have a small (200kb) mp3 in the res/raw folder of my android app. I am trying to run it in an emulator from ... e) { // handle this later } See Question&Answers more detail:os...

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c++ - Inheritance and method overloading

Why C++ compiler gives this error? Why i can access lol() from B, but can not access rofl() [without ... not take 0 arguments return 0; } See Question&Answers more detail:os...

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Extract Values between two strings in a text file using python

Lets say I have a Text file with the below content fdsjhgjhg fdshkjhk Start Good Morning Hello World End dashjkhjk ... . Excluding Start & End. See Question&Answers more detail:os...

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c++ - Why does same_as concept check type equality twice?

Looking at the possible implementation of the same_as concept at https://en.cppreference.com/w/cpp/concepts/same_as i ... ? Isn't it redundant? See Question&Answers more detail:os...

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html - HTML5 Video / End of a Video Poster

<video controls="controls" poster="http://gifs.gifbin.com/1233925271_8be9acc.gif" style="width:800px;"> With ... the video has played through? See Question&Answers more detail:os...

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Why doesn't str.translate work in Python 3?

Why does 'a'.translate({'a':'b'}) return 'a' instead of 'b'? I'm using Python 3. See Question&Answers more detail:os...

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c# - async/await keywords not available in .net 4.0

I would like to use the async/await in C# 4.0 and I have installed the following package: http://www.nuget ... am using VS2010 with SP1. Thanks. See Question&Answers more detail:os...

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C++: Is it safe to cast pointer to int and later back to pointer again?

Is it safe to cast pointer to int and later back to pointer again? How about if we know if the pointer is ... Is this covered by the Standard? See Question&Answers more detail:os...

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android - NoClassDefFoundError at Google Play Services V2 library

I get the following exception when trying to use the Google Play Services V2 library after following the official tutorial ... did I go wrong? See Question&Answers more detail:os...

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windows - Programmatically change screen resolution?

Is there a way to programmatically change the screen resolution or enable/disable multiple monitors in Windows XP ... shortcut would suffice. See Question&Answers more detail:os...

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user interface - How to convert a normal java project in intellij into a JavaFx project

I am currently using a normal java project (gradle project) and want to convert this into a JavaFx project without ... any way to achieve this? See Question&Answers more detail:os...

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c# - Is a reference assignment threadsafe?

I'm building a multi threaded cache in C#, which will hold a list of Car objects: public static IList<Car ... lock around getting and settings. See Question&Answers more detail:os...

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python - Matplotlib runs out of memory when plotting in a loop

I have a fairly simple plotting routine that looks like this: from __future__ import division import datetime import ... on my graphs... See Question&Answers more detail:os...

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python - How do I read an image from a path with Unicode characters?

I have the following code and it fails, because it cannot read the file from disk. The image is always None ... 's unrelated to Unicode issues. See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

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