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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...
Recommended: Declare your variables, for example when you try to append a string to an undefined variable. Or use isset() / !empty() to check if they are declared before referencing them, as in:
//Initializing variable
$value = ""; //Initialization value; Examples
//"" When you want ...
PHP: How to remove specific element from an array?
...ther 'strawberry' to demonstrate that it removes multiple instances of the string
$array_without_strawberries = array_diff($array, array('strawberry'));
print_r($array_without_strawberries);
...No need for extra functions or foreach loop.
...
How can I convert JSON to CSV?
... is as easy as using two commands!
pandas.read_json()
To convert a JSON string to a pandas object (either a series or dataframe). Then, assuming the results were stored as df:
df.to_csv()
Which can either return a string or write directly to a csv-file.
Based on the verbosity of previous ans...
Difference between attr_accessor and attr_accessible
...stname" and "role" :
SQL instructions :
CREATE TABLE users (
firstname string,
lastname string
role string
);
I assumed that you set the option config.active_record.whitelist_attributes = true in your config/environment/production.rb to protect your application from Mass assignment exploit...
Automatic vertical scroll bar in WPF TextBlock?
...cyProperty.RegisterAttached(
"AppendText",
typeof (string),
typeof (TextBoxApppendBehaviors),
new UIPropertyMetadata(null, OnAppendTextChanged));
public static string GetAppendText(TextBox textBox)
{
return (string)textBox.GetValue(App...
How to redirect to a dynamic login URL in ASP.NET MVC
...site which hosts pages for clients. The first segment of the URL will be a string which identifies the client, defined in Global.asax using the following URL routing scheme:
...
In Python, how do I determine if an object is iterable?
...
Checking for __iter__ works on sequence types, but it would fail on e.g. strings in Python 2. I would like to know the right answer too, until then, here is one possibility (which would work on strings, too):
from __future__ import print_function
try:
some_object_iterator = iter(some_object)...
How do I check if a string is unicode or ascii?
What do I have to do in Python to figure out which encoding a string has?
11 Answers
1...
Any way to make a WPF textblock selectable?
...Pointer StartSelectPosition;
TextPointer EndSelectPosition;
public String SelectedText = "";
public delegate void TextSelectedHandler(string SelectedText);
public event TextSelectedHandler TextSelected;
protected override void OnMouseDown(MouseButtonEventArgs e)
{
b...
How do I display an alert dialog on Android?
...ismissed when a dialog button is clicked.
.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// Continue with delete operation
}
})
// A null listener allows the button t...