流程控制-遍历数组元素
对数组中的每个元素执行操作
问题背景
对数组中的每个元素执行操作。例如，给定一个数字数组，将每个值四舍五入到最接近的整数。
解决方案
消息拆分 节点可用于将数组中的每个元素拆分成单独的消息。它后面可以跟操作各个元素所需的节点， 比如本示例使用 范围映射 节点， 对接受到的小数进行按相近整数取整，然后跟 消息合并 节点，用于将拆分的单个元素重新组合成素组。
示例
注入 节点负责给 msg.payload 设置一个浮点数数组： [1.67,2.98,3.12,4.99,5.50]
消息拆分节点 负责将数组中的每个元素拆分成单独的消息。
范围映射节点 负责对接收到的小数进行按相近整数取整。
消息合并节点 负责将拆分的单个元素重新组合成数组。
可以在此节点后连接一个 日志输出 节点，点击 注入 按钮时可以看到数组中的每个元素被拆分为单独的消息
示例JSON
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运行结果
整个控制流就是对给定的 msg.payload 的浮点数数组：拆分-对单个元素取整-合并
