EXE.pythonEval: Difference between revisions

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Calls to EXE.pythonEval are processed asynchronously. To return values, put {callback}(value) in your code, and supply the name of the function you want called as ''callback''.
Calls to EXE.pythonEval are processed asynchronously. To return values, put {callback}(value) in your code, and supply the name of the function you want called as ''callback''.


The length of the code string is limited - perhaps just 100-200 characters. However, the return data can be much larger.
The length of the code string is limited -around 220 characters. However, the return data can be much larger.


== Example (BASIC) ==
== Example (BASIC) ==

Revision as of 14:08, 1 June 2017

EXE.pythonEval(code[, callback])

Description

EXE.pythonEval executes code in the EXE runtime wrapper. It only works in EXE apps. AppStudio's EXE apps work by wrapping your app in a executable wrapper which is written in Python. This function requires you to know Python to use it.

Code has to be properly formatted Python code, following all Python syntax rules. In addition to the base Python language, the following libraries can be used:

  • os
  • wx
  • jason
  • yaml

Others may be included in a future release.

Calls to EXE.pythonEval are processed asynchronously. To return values, put {callback}(value) in your code, and supply the name of the function you want called as callback.

The length of the code string is limited -around 220 characters. However, the return data can be much larger.

Example (BASIC)

Do a simple calculation and return the result

EXE.pythonEval("{callback}(4*4)", "showResult")

Function showResult(res)
  MsgBox res
End Function

Example (JavaScript)

EXE.pythonEval("{callback}(4*4)", "showResult");

function showResult(res) {
    NSB.MsgBox(res);
}

Other examples

Exit the app

EXE.pythonEval("sys.exit(0)")

Put up a wx Message Box:

EXE.pythonEval("wx.MessageBox('It works!', 'Info', wx.OK | wx.ICON_INFORMATION)", "MessageBox")

Run a code snippet. Put the following code into a TextArea:

# Code must be in Python.
# note how to return results.
a=64
{callback}(a*a)

And execute it as follows:

EXE.pythonEval(TextArea1.value, "showResult")

Get a list of files in the current directory (BASIC):

EXE.pythonEval("{callback}('\r'.join(os.listdir('./')))", "showResult")
Function showResult(res)
  TextArea1.text = res
End Function

Get a list of files in the current directory (JavaScript):

EXE.pythonEval("{callback}('\\r'.join(os.listdir('./')))", "showResult");
function showResult(res) {
    TextArea1.text = res;
}

Read a file. (Also: Send multiple lines of code to Python.) (BASIC)

s = "file = open('./package.json')" & vbCRLF
s += "{callback}(file.read())"
EXE.pythonEval(s, "showResult") 

Read a file. (Also: Send multiple lines of code to Python.) (JavaScript)

s = "file = open('./package.json')" + '\n';
s += "{callback}(file.read())";
EXE.pythonEval(s, "showResult");

Output

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