How to copy code from Mathematica so it looks good on this site

Question

Many newcomers to this site have code that they entered into their notebooks using one of tje Mathematica palettes, e.g., Basic Math Assistant. They are delighted with mathematical look of their code, but when they copy such code from their notebook and paste into our editor, they often get a mess they don't know how to deal with. So they just leave the mess or they resort to making a PNG image of their code and posting that.

When they are chided by a community member for posting their code in a bad format, they are often given the advice to copy the code as plain text. My experience is that such advice is not optimal. What would constitute better advice?

Answer 1

Here is the way I do it when I have fancy standard form code I want post on Mathematica.SE

Step-by-step

1. Make a copy of the cell containing the code to be posted

2. Convert the copied cell to raw input form

   Choose Convert To > Raw InputForm from the Cell menu or from the contextual (right mouse clidk) menu

3. Select the code and do a normal copy (do not use Copy As)
4. Paste form the clipboard in the Mathematica.SE editor pane
5. Delete the raw input form cell from the notebook.

How it looks in a notebook

Update

This is aimed at newcomers. After you have pasted your code into an editor input pane, you are not done. The code must be block indented by a minimum of four spaces for the editor to recognize that it is code.

Here is some properly indented code without a block indent. It looks terrible because it is displayed without its line breaks and with all the leading indents are compressed to one space.

With[{n = 524}, xpts = Table[{i h, x[i]}, {i, 0, n}]; ypts = Table[{i h, y[i]}, {i, 0, n}];]

After carrying out the simple instructions given below, it looks good.

With[{n = 524},
  xpts = Table[{i h, x[i]}, {i, 0, n}];
  ypts = Table[{i h, y[i]}, {i, 0, n}];]

One way to make a block indent is to use the { } tool from the editor tool bar

1. Select the text you want to block indent
2. Click on the { } icon in the tool bar at the top of the editor input pane

The keyboard shortcut for clicking on the { } tool is Ctrl+K.

2nd update

Response to xzczd's comment

The cells produced are quite different.

InputForm

Cell[BoxData[
  RowBox[{"Sum", "[", 
    RowBox[{
      RowBox[{
        RowBox[{"Log", "[", "i", "]"}], "/", 
        RowBox[{"i", "^", "2"}]}], ",", " ", 
      RowBox[{"{", 
        RowBox[{"i", ",", " ", "1", ",", " ", "Infinity"}], "}"}]}], "]"}]], "Input",
  FormatType->"InputForm"]

Raw InputForm

Cell["Sum[Log[i]/i^2, {i, 1, Infinity}]", "Input"]

InputForm allows code coloring and other code editor formatting, but Raw InputForm is cleaner and to my mind better for copy and paste.