# Dynamic Dose Count Label (动态剂数标签)

## Feature
Made the dose count label dynamic based on the selected dose unit. When the user selects a different unit (剂/丸/袋/盒/瓶/膏/贴), the label automatically updates to match.

## Changes Made

### File: `admin/src/views/consumer/prescription/order_list.vue`

#### 1. Added Computed Property
Added a computed property that generates the label dynamically:

```typescript
// 动态剂数标签（根据剂量单位变化）
const doseCountLabel = computed(() => {
    const unit = editForm.dose_unit || '剂'
    return `${unit}数`
})
```

#### 2. Updated Form Item Label
Changed from static label to dynamic computed property:

**Before:**
```vue
<el-form-item label="剂数" prop="dose_count">
    <el-input-number
        v-model="editForm.dose_count"
        :min="1"
        placeholder="剂数"
        class="w-full"
    />
</el-form-item>
```

**After:**
```vue
<el-form-item :label="doseCountLabel" prop="dose_count">
    <el-input-number
        v-model="editForm.dose_count"
        :min="1"
        :placeholder="doseCountLabel"
        class="w-full"
    />
</el-form-item>
```

## How It Works

### Label Generation Logic
```typescript
const unit = editForm.dose_unit || '剂'  // Get current unit, default to '剂'
return `${unit}数`                        // Append '数' to create label
```

### Examples

| Selected Unit | Label Display |
|---------------|---------------|
| 剂            | 剂数          |
| 丸            | 丸数          |
| 袋            | 袋数          |
| 盒            | 盒数          |
| 瓶            | 瓶数          |
| 膏            | 膏数          |
| 贴            | 贴数          |

### Reactive Updates
The label updates automatically when:
1. User selects a different dose unit from the dropdown
2. Form is loaded with existing data
3. Form is reset or cleared

## User Experience

### Before:
- Label always shows "剂数" regardless of selected unit
- Confusing when unit is "贴" but label says "剂数"

### After:
- Label dynamically matches the selected unit
- Shows "贴数" when unit is "贴"
- Shows "丸数" when unit is "丸"
- More intuitive and consistent

## Implementation Details

### Computed Property Benefits
1. **Reactive**: Automatically updates when `editForm.dose_unit` changes
2. **Efficient**: Only recalculates when dependency changes
3. **Clean**: No need for watchers or manual updates

### Default Value
Uses `'剂'` as default when `dose_unit` is empty or undefined:
```typescript
const unit = editForm.dose_unit || '剂'
```

### Placeholder Update
Also updated the placeholder to match the label:
```vue
:placeholder="doseCountLabel"
```

This ensures consistency between the label and placeholder text.

## Testing Steps

### 1. Test Label Changes
1. Open order edit dialog
2. Check initial label (should be "剂数" if dose_unit is "剂")
3. Change dose unit to "贴"
4. Verify label changes to "贴数"
5. Try all other units and verify labels update correctly

### 2. Test with Existing Data
1. Edit an order that has dose_unit = "丸"
2. Verify label shows "丸数" when dialog opens
3. Change to different unit
4. Verify label updates immediately

### 3. Test Default Behavior
1. Create a new order (dose_unit is empty)
2. Verify label shows "剂数" (default)
3. Select a unit
4. Verify label updates

### 4. Test Placeholder
1. Clear the dose_count field
2. Verify placeholder text matches the label
3. Change dose unit
4. Verify placeholder updates with label

## Edge Cases Handled

### Empty/Undefined Unit
```typescript
const unit = editForm.dose_unit || '剂'
```
Falls back to '剂' if unit is empty, null, or undefined.

### Form Reset
When form is reset, the computed property automatically recalculates based on the new (or default) value.

### Multiple Edits
Label updates correctly even when editing multiple orders in sequence without closing the dialog.

## Related Code

### Form Structure
```vue
<el-row :gutter="24">
    <el-col :span="12">
        <!-- Dynamic label based on dose_unit -->
        <el-form-item :label="doseCountLabel" prop="dose_count">
            <el-input-number v-model="editForm.dose_count" ... />
        </el-form-item>
    </el-col>
    <el-col :span="12">
        <!-- Dose unit selector -->
        <el-form-item label="剂量单位" prop="dose_unit">
            <el-select v-model="editForm.dose_unit" ...>
                <el-option label="剂" value="剂" />
                <el-option label="丸" value="丸" />
                <!-- ... other options ... -->
            </el-select>
        </el-form-item>
    </el-col>
</el-row>
```

### Data Flow
```
User selects dose_unit → editForm.dose_unit changes → 
doseCountLabel computed property recalculates → 
Label and placeholder update in UI
```

## Future Enhancements

### Possible Improvements
1. **Validation Message**: Update validation messages to use dynamic unit
2. **Display in Detail View**: Show unit-specific label in order detail view
3. **Internationalization**: Support multiple languages for unit names
4. **Custom Units**: Allow admin to configure custom dose units

### Example: Dynamic Validation
```typescript
const doseCountRules = computed(() => [
    { required: true, message: `请输入${editForm.dose_unit || '剂'}数`, trigger: 'blur' }
])
```

## Summary

✅ Added dynamic label that changes based on selected dose unit  
✅ Label updates automatically when unit changes  
✅ Placeholder also updates to match label  
✅ Default to "剂数" when unit is empty  
✅ Handles all 7 dose units (剂/丸/袋/盒/瓶/膏/贴)  
✅ Reactive and efficient using computed property  
✅ Better user experience with consistent terminology  

The dose count label now dynamically reflects the selected unit, making the form more intuitive and user-friendly!