angularjs - Why does ng-click not work in case-1, but does in case-3?

Question

There is clearly something fundamental im not yet understanding.

Im trying to make user of the Modal module in Angular Ui.Bootstrap but im finding that my clicks are not activating the open() function -- So boiling it down to a very simple testcase, as below, im not seeing any calls when the ng-click points to a function (alert or console.log), but does work when the ng-click points to something which is just an expression

Why is the alert not called in the first example?

<div data-ng-app>
    <button data-ng-click="alert('Message 1');">
        ngClick -- not working, why not?
    </button>
    <button onclick="alert('Message 2');">
        Plain onclick
    </button>
    <button data-ng-click="count = (count + 1)">
          But this works, why ???
    </button>
    count: {{count}}
</div>

http://jsfiddle.net/H2wft/1/

question from:https://stackoverflow.com/questions/23725312/why-does-ng-click-not-work-in-case-1-but-does-in-case-3

Answer 1

ng-click is meant for use with either a function in the current scope (so for example $scope.alert = window.alert would solve the problem of not being able to alert there) or an angular expression. it looks like angular does not allow you to use global scope methods in there (it might be looking them up in the current $scope, from which they are missing).