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Why is Java Vector (and Stack) class considered obsolete or deprecated?

Why is Java Vector considered a legacy class, obsolete or deprecated? Isn't its use valid when working with concurrency ... , what should I use instead of it? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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Excel VBA, getting range from an inactive sheet

This script works fine when I'm viewing the "Temp" sheet. But when I'm in another sheet then the copy command fails. ... sheet to get this. What else can I do? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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175 views

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html - Hide scroll bar, but while still being able to scroll

I want to be able to scroll through the whole page, but without the scrollbar being shown. In Google Chrome it's ... whole page? With just CSS or HTML, please. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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ios - Transport security has blocked a cleartext HTTP

What setting do I need to put in my info.plist to enable HTTP mode as per the following error message? ... file. Assume that my domain is example.com. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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javascript - Uncaught ReferenceError: $ is not defined?

How come this code throws an Uncaught ReferenceError: $ is not defined when it was OK before? $(document).ready( ... -personalized-1.5.2.packed.js"></script> Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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c - How dangerous is it to access an array out of bounds?

How dangerous is accessing an array outside of its bounds (in C)? It can sometimes happen that I read from outside the ... safely? I use OSX 10.7, Xcode 4.6. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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How can I convert an image into Base64 string using JavaScript?

I need to convert my image to a Base64 string so that I can send my image to a server. Is there any JavaScript file for this? Else, how can I convert it? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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new operator - What is the 'new' keyword in JavaScript?

The new keyword in JavaScript can be quite confusing when it is first encountered, as people tend to think that ... solve? When is it appropriate and when not? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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ios - What are Unwind segues for and how do you use them?

iOS 6 and Xcode 4.5 has a new feature referred to as "Unwind Segue": Unwind segues can allow transitioning to ... segues work and what they can be used for? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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python - Accessing the index in 'for' loops?

How do I access the index in a for loop like the following? ints = [8, 23, 45, 12, 78] for i in ints: ... access the loop index, from 1 to 5 in this case? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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sql - What is the most efficient/elegant way to parse a flat table into a tree?

Assume you have a flat table that stores an ordered tree hierarchy: Id Name ParentId Order 1 'Node 1' 0 10 2 ... solution so you guys can pull it to pieces. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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javascript - How to round to at most 2 decimal places, if necessary?

I'd like to round at most 2 decimal places, but only if necessary. Input: 10 1.7777777 9.1 Output: 10 1.78 9.1 How can I do this in JavaScript? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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1 answer

c# - Get property value from string using reflection

I am trying implement the Data transformation using Reflection1 example in my code. The GetSourceValue function ... Web Archive version of original blog post Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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Calculate a Running Total in SQL Server

Imagine the following table (called TestTable): id somedate somevalue -- -------- --------- 45 01/Jan/ ... with the setup and the 'update trick' example above Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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Is it possible to escape regex metacharacters reliably with sed

I'm wondering whether it is possible to write a 100% reliable sed command to escape any regex metacharacters in ... and probably break and/or elaborate them. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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311 views

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php - How to Flatten a Multidimensional Array?

Is it possible, in PHP, to flatten a (bi/multi)dimensional array without using recursion or references? I'm ... the lines of array_map() and array_values(). Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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250 views

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r - ggplot with 2 y axes on each side and different scales

I need to plot a bar chart showing counts and a line chart showing rate all in one chart, I can do both of ... I move the axis of the geom_line to the right? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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1 answer

r - Simultaneously merge multiple data.frames in a list

I have a list of many data.frames that I want to merge. The issue here is that each data.frame differs in ... no resolution). Is there any way to solve this? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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102 views

1 answer

python - How do you append to a file?

How do you append to the file instead of overwriting it? Is there a special function that appends to the file? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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332 views

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Android 8: Cleartext HTTP traffic not permitted

I had reports from users with Android 8 that my app (that uses back-end feed) does not show content. ... Google info about Android O, but without success. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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151 views

1 answer

How to merge two arrays in JavaScript and de-duplicate items

I have two JavaScript arrays: var array1 = ["Vijendra","Singh"]; var array2 = ["Singh", "Shakya"]; ... same order they were inserted into the original arrays? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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227 views

1 answer

dom - How do I get the value of text input field using JavaScript?

I am working on a search with JavaScript. I would use a form, but it messes up something else on my page ... get the value from the text field into JavaScript? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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112 views

1 answer

php - mysqli or die, does it have to die?

If I use a bit of code like this: $update_result = mysqli_query( $link , $sql_update_login ) or die (' ... in the documentation, any clues are appreciated. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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r - Split data frame string column into multiple columns

I'd like to take data of the form before = data.frame(attr = c(1,30,4,6), type=c('foo_and_bar',' ... pointers. I've not quite groked R lists just yet. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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64 views

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android - Ship an application with a database

If your application requires a database and it comes with built in data, what is the best way to ... regarding any issues would be greatly appreciated. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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127 views

1 answer

javascript - Why is setTimeout(fn, 0) sometimes useful?

I've recently run into a rather nasty bug, wherein the code was loading a <select> dynamically via ... calling my function "later" using setTimeout()? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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114 views

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How do function pointers in C work?

I had some experience lately with function pointers in C. So going on with the tradition of answering your own ... need a quick dive-in to the subject. Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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python - Iterating over dictionaries using 'for' loops

I am a bit puzzled by the following code: d = {'x': 1, 'y': 2, 'z': 3} for key in d: print (key ... Is key a special word in Python? Or is it simply a variable? Question&Answers:os...

asked Oct 16, 2021 in Technique[技术] by 深蓝 (71.8m points)

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