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this.setState isn't merging states as I would expect
...he value of the current state this.state.selected to construct a new state and then call setState() on that:
var newSelected = _.extend({}, this.state.selected);
newSelected.name = 'Barfoo';
this.setState({ selected: newSelected });
I've used function _.extend() function (from underscore.js libra...
What's the difference between HEAD^ and HEAD~ in Git?
...f thumb
Use ~ most of the time — to go back a number of generations, usually what you want
Use ^ on merge commits — because they have two or more (immediate) parents
Mnemonics:
Tilde ~ is almost linear in appearance and wants to go backward in a straight line
Caret ^ suggests an interesting s...
How do I see what character set a MySQL database / table / column is?
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This should be merged in the top answer. It really helped me.
– beppe9000
Jan 14 '17 at 16:55
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How to convert IPython notebooks to PDF and HTML?
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If you have LaTeX installed you can download as PDF directly from Jupyter notebook with File -> Download as -> PDF via LaTeX (.pdf). Otherwise follow these two steps.
For HTML output, you should now use Jupyter in place of IPython and sele...
How to check if a file is a valid image file?
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That won't be sufficient if he's really testing for "valid" images; the presence of a magic number doesn't guarantee that the file hasn't been truncated, for example.
– Ben Blank
May 20 '09 at 18:11
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Are there disadvantages to using a generic varchar(255) for all text-based fields?
... (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
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Jackson Vs. Gson [closed]
...pe information)
Integrated support for binary content (base64 to/from JSON Strings)
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How do you save/store objects in SharedPreferences on Android?
...Object', etc.
Editor prefsEditor = mPrefs.edit();
Gson gson = new Gson();
String json = gson.toJson(myObject);
prefsEditor.putString("MyObject", json);
prefsEditor.commit();
To retrieve:
Gson gson = new Gson();
String json = mPrefs.getString("MyObject", "");
MyObject obj = gson.fromJson(json, My...
Can you get the column names from a SqlDataReader?
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var reader = cmd.ExecuteReader();
var columns = new List<string>();
for(int i=0;i<reader.FieldCount;i++)
{
columns.Add(reader.GetName(i));
}
or
var columns = Enumerable.Range(0, reader.FieldCount).Select(reader.GetName).ToList();
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Rails Object to hash
...ly attributes, then you can get them by:
@post.attributes
Note that this calls ActiveModel::AttributeSet.to_hash every time you invoke it, so if you need to access the hash multiple times you should cache it in a local variable:
attribs = @post.attributes
...