mybatis if 标签 判断不生效

mybatis if 标签 判断不生效

实际需求:

<if test="vinOrNum != null and vinOrNum != '' and vinOrNum =='1'">
  vin = #{emallOrderOrVin}
if>
<if test="vinOrNum != null and vinOrNum != '' and vinOrNum =='2'">
  emall_order_num = #{emallOrderOrVin}
if>

这种情况不生效,
原因:mybatis是用OGNL表达式来解析的,在OGNL的表达式中,'0’会被解析成字符,java是强类型的,char 和 一个string 会导致不等,所以if标签中的sql不会被解析。

标签同样 有其问题

解决方式

三种:
1.加 .toString()

 <if test="vinOrNum != null and vinOrNum != '' and vinOrNum =='1'.toString()">
            vin = #{emallOrderOrVin}
        if>
        <if test="vinOrNum != null and vinOrNum != '' and vinOrNum =='2'.toString()">
            emall_order_num = #{emallOrderOrVin}
        if>

2.单引号 换成双引号

 <if test='vinOrNum != null and vinOrNum =="1"'>
            vin = #{emallOrderOrVin}
        if>
        <if test='vinOrNum != null and vinOrNum =="2"'>
            emall_order_num = #{emallOrderOrVin}
        if>

3…java 传值为 数值类型 Integer int之类的

 <if test="vinOrNum != null and vinOrNum != '' and vinOrNum ==1 ">
            vin = #{emallOrderOrVin}
        if>
        <if test="vinOrNum != null and vinOrNum != '' and vinOrNum ==2 ">
            emall_order_num = #{emallOrderOrVin}
        if>

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