Question

我在这个fiddle中使用指令和=绑定。我收到以下错误：

Uncaught Error: 10 $digest() iterations reached. Aborting!
Watchers fired in the last 5 iterations: [["fn: function () {\n                  var parentValue = parentGet(parentScope);\n\n                  if (parentValue !== scope[scopeName]) {\n                    // we are out of sync and need to copy\n                    if (parentValue !== lastValue) {\n                      // parent changed and it has precedence\n                      lastValue = scope[scopeName] = parentValue;\n                    } else {\n                      // if the parent can be assigned then do so\n                      parentSet(parentScope, lastValue = scope[scopeName]);\n                    }\n                  }\n                  return parentValue;\n                }; newVal: {\"baz\":3}; oldVal: {\"baz\":3}"],["fn: function () {\n                  var parentValue = parentGet(parentScope);\n\n                  if (parentValue !== scope[scopeName]) {\n                    // we are out of sync and need to copy\n                    if (parentValue !== lastValue) {\n                      // parent changed and it has precedence\n                      lastValue = scope[scopeName] = parentValue;\n                    } else {\n                      // if the parent can be assigned then do so\n                      parentSet(parentScope, lastValue = scope[scopeName]);\n                    }\n                  }\n                  return parentValue;\n                }; newVal: {\"baz\":3}; oldVal: {\"baz\":3}"],["fn: function () {\n                  var parentValue = parentGet(parentScope);\n\n                  if (parentValue !== scope[scopeName]) {\n                    // we are out of sync and need to copy\n                    if (parentValue !== lastValue) {\n                      // parent changed and it has precedence\n                      lastValue = scope[scopeName] = parentValue;\n                    } else {\n                      // if the parent can be assigned then do so\n                      parentSet(parentScope, lastValue = scope[scopeName]);\n                    }\n                  }\n                  return parentValue;\n                }; newVal: {\"baz\":3}; oldVal: {\"baz\":3}"],["fn: function () {\n                  var parentValue = parentGet(parentScope);\n\n                  if (parentValue !== scope[scopeName]) {\n                    // we are out of sync and need to copy\n                    if (parentValue !== lastValue) {\n                      // parent changed and it has precedence\n                      lastValue = scope[scopeName] = parentValue;\n                    } else {\n                      // if the parent can be assigned then do so\n                      parentSet(parentScope, lastValue = scope[scopeName]);\n                    }\n                  }\n                  return parentValue;\n                }; newVal: {\"baz\":3}; oldVal: {\"baz\":3}"],["fn: function () {\n                  var parentValue = parentGet(parentScope);\n\n                  if (parentValue !== scope[scopeName]) {\n                    // we are out of sync and need to copy\n                    if (parentValue !== lastValue) {\n                      // parent changed and it has precedence\n                      lastValue = scope[scopeName] = parentValue;\n                    } else {\n                      // if the parent can be assigned then do so\n                      parentSet(parentScope, lastValue = scope[scopeName]);\n                    }\n                  }\n                  return parentValue;\n                }; newVal: {\"baz\":3}; oldVal: {\"baz\":3}"]] angular.js:7729
Scope.$digest angular.js:7729
Scope.$apply angular.js:7894
(anonymous function) angular.js:930
invoke angular.js:2788
bootstrap angular.js:928
angularInit angular.js:904
(anonymous function) angular.js:14397
trigger angular.js:1695
(anonymous function) angular.js:1930
forEach angular.js:110
eventHandler angular.js:1929

为什么会这样？我认为它与=绑定有关。

Answer 1

这是因为它每次进入摘要周期时都会创建一个全新的对象。手表在此=数据绑定中注册，因此每次评估bar="{baz: 3}"时，都会创建一个新对象，因此它将与之前的值不同，从而触发另一个摘要循环。最终它会中止，因此它不会无限循环。有关详细说明，请参阅http://docs.angularjs.org/guide/concepts#runtime。

诀窍是使用每次都不会改变的引用进行=数据处理。这通常通过将其置于指令范围之外的范围内来完成。见http://jsfiddle.net/u4BTu/7/

Answer 2

有一种方法可以在HTML模板上实现对象文字表达式：

<div my-directive="{ param: 34, param2: 'cool' }" another-param="parentScopeObject"></div>

var directiveFunction = function(){
    return {
        scope: {
            myDirective: '&',
            anotherParam: '&'
        },
        link: function(scope, element, attributes){

            //this will return the actual object from the object expression!
            console.log(scope.myDirective());
            //this will return the actual object from the parent scope, if it exists of course!
            //and no "parentScopeObject" is not a function, it's an object
            console.log(scope.anotherParam());

        }
    };
}

这是从我的Angular绑定示例列表中提取的。见第6项：https://gist.github.com/CMCDragonkai/6282750

Answer 3

将此代码添加到您的应用程序定义或app.js中这将增加digestTtl以进行应用。

yourApp.config(function ($rootScopeProvider) {
       $rootScopeProvider.digestTtl(15); 
       // 15 is int value, just set to more than 10. If not works justincrement it bye one every-time and refresh page to test
  })

最大化$ digest迭代

3 个答案: