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How can I validate a string to only allow alphanumeric characters in it?
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I detest regular expressions. I know that I will never remember the syntax. Even if I study it, there will come a time soon when it's all forgotten again.
– Sentinel
Jan 14 '15 at 17:26
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Is ASCII code 7-bit or 8-bit?
...he 8th bit of each byte of text for its own purposes ("not 8-bit clean"). Nowadays people think of it as an 8-bit coding in which bytes 0x80 through 0xFF have no defined meaning, but that's a retcon.
There are dozens of text encodings that make use of the 8th bit; they can be classified as ASCII-c...
Rails create or update magic?
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Oh... I see what you meant now - that both forms, find_or_initialize_by and find_or_create_by accept a block. I thought you meant that whether the record exists or not, a block will be passed down with the record object as an argument, in order to do t...
MySQL: #126 - Incorrect key file for table
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First of all, you should know that keys and indices are synonyms in MySQL. If you look at the documentation about the CREATE TABLE Syntax, you can read:
KEY is normally a synonym for INDEX. The key attribute PRIMARY KEY can also be specified as ju...
Stop form refreshing page on submit
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Super old thread, but for anybody who comes across this now, please do not try action="#" because it does not work and is not an appropriate solution. The key is actually onsubmit="yourJsFunction();return false"
– Jeff
Nov 9 '19 at 21:04
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Method call if not null in C#
...void SafeInvoke(this Action action) {
if(action != null) action();
}
now this is valid:
Action act = null;
act.SafeInvoke(); // does nothing
act = delegate {Console.WriteLine("hi");}
act.SafeInvoke(); // writes "hi"
In the case of events, this has the advantage of also removing the race-con...
How to change folder with git bash?
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Is there a way to save long directories? I know cd $USER will bring me to my users directory on windows.
– meiryo
Aug 3 '13 at 16:14
1
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How do I run a Java program from the command line on Windows?
... saved your file as A.text first thing you should do is save it as A.java. Now it is a Java file.
Now you need to open cmd and set path to you A.java file before compile it. you can refer this for that.
Then you can compile your file using command
javac A.java
Then run it using
java A
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Why should you remove unnecessary C# using directives?
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Now that's what I wanted to hear :-) I am used doing a Organize Usings -> Remove and Sort every now and then. BTW, to me the upper two options in Organize Usings are meaningless. I am talking about VS2013 btw.
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Accessing inactive union member and undefined behavior?
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To make this complete, you need to know what "layout-compatible types" are for C++, or "compatible types" are for C.
– Michael Anderson
Aug 15 '12 at 8:32
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