将参数传递给匿名函数

Question

i try to undestand the scope of this wrapped function.

  componentWillMount = () => {
    //-----------------------
    // props accesible here:
    //-----------------------
    console.log(this.props);
    $(function() {
      var jqconsole = $('#console').jqconsole('Welcome to the console!\n', '>');
      jqconsole.Write(
        //-----------------------
        // props inaccesible here:
        //-----------------------
        this.getMessagesFromJavascriptWindow(this.props.code) + '\n',
        'jqconsole-output'
      );
      var startPrompt = function() {
        // Start the prompt with history enabled.
        jqconsole.Prompt(true, function(input) {
          let transformedString;
          try {
            transformedString = eval(input);
            // Output input with the class jqconsole-output.
            jqconsole.Write(transformedString + '\n', 'jqconsole-output');
            // Restart the input prompt.
            startPrompt();
          } catch (error) {
            jqconsole.Write(error + '\n', 'jqconsole-output-error');
            // Restart the input prompt.
            startPrompt();
          }
        });
      };
      // Restart the input prompt.
      startPrompt();
    });
  };

I am new to JQuery. I need to pass an argument to this anonymous function while using the JQuery wrapper. Can somebody explain this or show me corresponding docs? I did not find it.

edit:

For some context: What i am doing is happening in a React components componentWillMount method. And i am trying to access the props.

Answer 1

Make sure the context where you call your function knows of test, otherwise you obviously will not be able to pass something you don't know.

Then proceed like this:

var self = this;
$(function( self ){ can access this.props here via self.props })

You can always pass parameters to anonymous functions, but the context where you call them needs to know about these parameters. This is also how deferred works:

/** define in some context */
var dfd = $.Deferred();
dfd.resolve( 5 );

/** define in some other context, that knows of the dfd above */
dfd.done( function ( param ) { console.log( param ); });

// result: 5

With respect to your edit:

var self = this; // before calling the anonymous function

Then use

self.props

in the anonymous function.

EDIT: I think in your case you don't even need to pass any parameters. All you need is to take care of this . When in doubt, save a context to a variable.