feat: 订单创建页面商品数量支持+号-号，且不超过库存

src/pages/order/create.vue

@@ -53,12 +53,17 @@
         <view class="item-edit">
           <view class="quantity-edit">
             <text class="qty-label">数量</text>
-            <input 
+            <view class="qty-wrapper">
-              class="qty-input" 
+              <text class="qty-btn" @click="qtyMinus(index)">-</text>
-              type="number" 
+              <input 
-              v-model="item.quantity" 
+                class="qty-input" 
-              @change="calcAmount"
+                type="number" 
-            />
+                v-model="item.quantity" 
+                @change="onQuantityChange(index)"
+              />
+              <text class="qty-btn" @click="qtyPlus(index)">+</text>
+            </view>
+            <text class="stock-info">库存: {{ stocks[item.productId] || 0 }}</text>
           </view>
           <view class="price-edit">
             <text class="qty-label">单价</text>
@@ -175,6 +180,7 @@
 
 <script>
 import orderApi from '@/api/order'
+import stockApi from '@/api/stock'
 import productApi from '@/api/product'
 import customerApi from '@/api/customer'
 
@@ -198,6 +204,7 @@ export default {
       orderItems: [],
       productList: [],
       searchKeyword: '',
+      stocks: {}, // 商品库存
       
       // 金额相关
       discountRate: 100,  // 折扣率（保留逻辑，默认100%不打折）
@@ -219,6 +226,7 @@ export default {
   onLoad(options) {
     this.loadCustomersByType()
     this.loadProducts()
+    this.loadStocks()
     if (options.orderId) {
       this.editingOrderId = options.orderId
       // 编辑模式
@@ -299,6 +307,20 @@ export default {
         console.error(e)
       }
     },
+    async loadStocks() {
+      try {
+        const res = await stockApi.getStockList({ page: 1, pageSize: 500 })
+        const stockMap = {}
+        if (res.records) {
+          res.records.forEach(s => {
+            stockMap[s.productId] = s.quantity || 0
+          })
+        }
+        this.stocks = stockMap
+      } catch (e) {
+        console.error(e)
+      }
+    },
     selectCustomer(e) {
       this.selectedCustomer = this.filteredCustomers[e.detail.value]
     },
@@ -350,6 +372,38 @@ export default {
       this.orderItems.splice(index, 1)
       this.calcAmount()
     },
+    qtyMinus(index) {
+      const item = this.orderItems[index]
+      const stock = this.stocks[item.productId] || 0
+      if (item.quantity > 1) {
+        item.quantity--
+        this.calcAmount()
+      }
+    },
+    qtyPlus(index) {
+      const item = this.orderItems[index]
+      const stock = this.stocks[item.productId] || 0
+      if (item.quantity < stock) {
+        item.quantity++
+        this.calcAmount()
+      } else {
+        uni.showToast({ title: '库存不足', icon: 'none' })
+      }
+    },
+    onQuantityChange(index) {
+      const item = this.orderItems[index]
+      const stock = this.stocks[item.productId] || 0
+      let qty = parseInt(item.quantity)
+      if (isNaN(qty) || qty < 1) {
+        qty = 1
+      }
+      if (qty > stock) {
+        qty = stock
+        uni.showToast({ title: '库存不足，已调整为最大库存', icon: 'none' })
+      }
+      item.quantity = qty
+      this.calcAmount()
+    },
     // 核心金额计算逻辑
     calcAmount() {
       // 1. 计算原价 = Σ(单价 × 数量)
@@ -555,16 +609,50 @@ export default {
   margin-right: 8rpx;
 }
 
-.qty-input, .price-input {
+.qty-wrapper {
-  width: 100rpx;
+  display: flex;
-  height: 56rpx;
+  align-items: center;
+  background: #f5f5f5;
+  border-radius: 8rpx;
+}
+
+.qty-btn {
+  width: 48rpx;
+  height: 48rpx;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 32rpx;
+  color: #667eea;
   background: #fff;
   border: 1rpx solid #ddd;
-  border-radius: 8rpx;
+}
+
+.qty-btn:first-child {
+  border-radius: 8rpx 0 0 8rpx;
+}
+
+.qty-btn:last-child {
+  border-radius: 0 8rpx 8rpx 0;
+}
+
+.qty-input {
+  width: 80rpx;
+  height: 48rpx;
+  background: #fff;
+  border: 1rpx solid #ddd;
+  border-left: none;
+  border-right: none;
   text-align: center;
   font-size: 24rpx;
 }
 
+.stock-info {
+  font-size: 20rpx;
+  color: #999;
+  margin-left: 12rpx;
+}
+
 .item-subtotal {
   flex: 1;
   text-align: right;