1# DFX Subsystem Changelog
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3## cl.hiviewdfx.1 Event Verification Specification Change for the write Method of the HiAppEvent Module
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5Extended the event verification specifications for the **write** method of the HiAppEvent module to support predefined events of HUAWEI Analytics. Specific changes are as follows:
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7  - The event name can start with a dollar sign ($) and can contain uppercase letters, lowercase letters, digits, and underscores (_). Before the change, the event name can contain lowercase letters, digits, and underscores (_).
8  - The event parameter name can start with a dollar sign ($) and can contain uppercase letters, lowercase letters, digits, and underscores (_). Before the change, the event parameter name can contain lowercase letters, digits, and underscores (_).
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10**Change Impact**
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12More event definition formats are supported for event logging.
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14**Key API/Component Changes**
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16Involved APIs:
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18  - hiAppEvent.write;
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20**Adaptation Guide**
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22The event verification specifications are downward compatible. No additional adaptation is required.
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