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Javascript 基于计数中断Object.keys循环_Javascript_Reactjs - Fatal编程技术网

Javascript 基于计数中断Object.keys循环

Javascript 基于计数中断Object.keys循环,javascript,reactjs,Javascript,Reactjs,我想在迭代前3个对象后中断循环。我可以为count设置变量,并使用filter在映射上执行增量,但有没有一种优雅的方法呢 Object.keys(data) .filter(key => !data[key].required) .map(function (key) { return <Greetings/> }); Object.key(数据) .filter(键=>!数据[key]。必需) .map(功能(键){ 返回 });

我想在迭代前3个对象后中断循环。我可以为count设置变量,并使用filter在映射上执行增量,但有没有一种优雅的方法呢

Object.keys(data)
    .filter(key => !data[key].required)
    .map(function (key) {
          return <Greetings/>
    });
Object.key(数据)
.filter(键=>!数据[key]。必需)
.map(功能(键){
返回
});

您可以在映射之前进行切片,以迭代前三个元素

Object.keys(data)
    .filter(key => !data[key].required)
    .slice(0, 3)
    .map(function (key) {
          return <Greetings/>
    });
Object.key(数据)
.filter(键=>!数据[key]。必需)
.slice(0,3)
.map(功能(键){
返回
});