(null)和<null>的区别

本文介绍了在Objective-C中NSNull类的使用场景及其与nil的不同之处。通过对比说明了(null)并不等于nil,并给出了具体的解释。

<null>的类是NSNull

(null)是!=nil

转载于:https://www.cnblogs.com/lsh1234/p/6484180.html

<insert id="insertMlbSmtPickQpl" parameterType="MlbSmtPickQpl" useGeneratedKeys="true" keyProperty="id"> insert into mlb_smt_pick_qpl <trim prefix="(" suffix=")" suffixOverrides=","> <if test="model != null">model,</if> <if test="site != null">site,</if> <if test="process != null">process,</if> <if test="lineName != null">line_name,</if> <if test="produceStationName != null">produce_station_name,</if> <if test="stationType != null">station_type,</if> <if test="equipmentType != null">equipment_type,</if> <if test="equipmentManu != null">equipment_manu,</if> <if test="equipmentModel != null">equipment_model,</if> <if test="ct != null">ct,</if> <if test="pickQpl != null">pick_qpl,</if> <if test="createTime != null">create_time,</if> <if test="createBy != null">create_by,</if> <if test="updateTime != null">update_time,</if> <if test="updateBy != null">update_by,</if> <if test="productType != null">product_type,</if> <if test="parentTaskNo != null">parent_task_no,</if> <if test="childTaskNo != null">child_task_no,</if> <if test="version != null">version,</if> <if test="actId != null">act_id,</if> </trim> <trim prefix="values (" suffix=")" suffixOverrides=","> <if test="model != null">#{model},</if> <if test="site != null">#{site},</if> <if test="process != null">#{process},</if> <if test="lineName != null">#{lineName},</if> <if test="produceStationName != null">#{produceStationName},</if> <if test="stationType != null">#{stationType},</if> <if test="equipmentType != null">#{equipmentType},</if> <if test="equipmentManu != null">#{equipmentManu},</if> <if test="equipmentModel != null">#{equipmentModel},</if> <if test="ct != null">#{ct},</if> <if test="pickQpl != null">#{pickQpl},</if> <if test="createTime != null">#{createTime},</if> <if test="createBy != null">#{createBy},</if> <if test="updateTime != null">#{updateTime},</if> <if test="updateBy != null">#{updateBy},</if> <if test="productType != null">#{productType},</if> <if test="parentTaskNo != null">#{parentTaskNo},</if> <if test="childTaskNo != null">#{childTaskNo},</if> <if test="version != null">#{version},</if> <if test="actId != null">#{actId},</if> </trim> </insert>改为foreach遍历写法
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07-19
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