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How do I check if file exists in jQuery or pure JavaScript?
...n('HEAD', url, false);
http.send();
return http.status!=404;
}
Small changes and it could check for status HTTP status code 200 (success), instead.
EDIT 2: Since sync XMLHttpRequest is deprecated, you can add a utility method like this to do it async:
function executeIfFileExist(src, cal...
When should I use perror(“…”) and fprintf(stderr, “…”)?
...should use fprintf(stderr, fmt, ...). For example, strtol will return LONG_MAX or LONG_MIN if a string is out of range and set errno to ERANGE. So if strtol fails due to out of range, I would use perror.
– freeboy1015
Aug 24 '12 at 2:22
...
Creating a blurring overlay view
...ize.height);
reOrient = CGAffineTransformRotate(reOrient, M_PI);
break;
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
reOrient = CGAffineTransformTranslate(reOrient, theImage.size.width, 0);
r...
Using ping in c#
... InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
Ping p = new Ping();
PingReply r;
string s;
s = textBox1.Text;
r = p.Send(s);
i...
How to drive C#, C++ or Java compiler to compute 1+2+3+…+1000 at compile time?
In a recent interview, I was asked a really strange question. The interviewer asked me how can I compute 1+2+3+...+1000 just using compiler features. This means that I am not allowed to write a program and execute it, but I should just write a program that could drive the compiler to compute this su...
Ruby Gem install Json fails on Mavericks and Xcode 5.1 - unknown argument: '-multiply_definedsuppres
I was trying run gem install json and got the following error
10 Answers
10
...
Maven: The packaging for this project did not assign a file to the build artifact
...ac 10.6.6. I have a JAR project and when I run the command "mvn clean install:install", I'm getting the error,
8 Answers
...
How do I get a TextBox to only accept numeric input in WPF?
...nly want to allow numbers, dots and dashes.
private static readonly Regex _regex = new Regex("[^0-9.-]+"); //regex that matches disallowed text
private static bool IsTextAllowed(string text)
{
return !_regex.IsMatch(text);
}
If you want to prevent pasting of incorrect data hook up the DataObj...
How do I verify that an Android apk is signed with a release certificate?
...oid\sdk\build-tools\25.0.3` (and every other build tools version I had installed)
– Jon
May 15 '17 at 20:17
2
...
What do the return values of node.js process.memoryUsage() stand for?
... Scheme first.
A running program is always represented through some space allocated in memory. This space is called Resident Set. V8 uses a scheme similar to the Java Virtual Machine and divides the memory into segments:
Code: the actual code being executed
Stack: contains all value types (prim...