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Mybatis結(jié)果生成鍵值對(duì)的實(shí)例代碼

發(fā)布時(shí)間：2020-09-13 06:04:14 來(lái)源：腳本之家 閱讀：161 作者：mrr 欄目：編程語(yǔ)言

下面給大家介紹下mybatis結(jié)果生成鍵值對(duì)的實(shí)例代碼，具體內(nèi)容如下所示：

在實(shí)際應(yīng)用中我們經(jīng)常會(huì)遇到這樣的情況，需要給下拉框賦值，這個(gè)時(shí)候就需要鍵值對(duì)了，具體使用方法如下

1，在maper.xml文件中定義結(jié)果類型(resultType)定義為hashmap,如下所示

<select id="selectSuperUnitInfo" resultType="hashmap">
  SELECT unit_id ,unit_name from unit_info
 </select>

2，在對(duì)應(yīng)的mapper類中用List<Map<String,String>>來(lái)接受這個(gè)類型，如下所示

public List<Map<String,String>> selectSuperUnitInfo();

其實(shí)最強(qiáng)大的莫過(guò)于resultMap類型了，這個(gè)可以在mapper.xml文件中自定義擴(kuò)展類型，然后在包中添加這個(gè)類型即可，真是強(qiáng)大

下面給大家補(bǔ)充下MyBatis返回Map鍵值對(duì)數(shù)據(jù)

List<Map<String, String>> getMtypeList();
<select id="getMtypeList" resultType="java.util.HashMap">
  select code,`name` from jk_control_measure
</select>
[DEBUG] 2016-08-29 17:50:09 :==> Executing: select code,`name` from jk_control_measure 
[DEBUG] 2016-08-29 17:50:09 :==> Parameters: 
[DEBUG] 2016-08-29 17:50:10 :<==  Columns: code, name
[DEBUG] 2016-08-29 17:50:10 :<==    Row: one, 地面沖洗
[DEBUG] 2016-08-29 17:50:10 :<==    Row: two, 邊界圍擋
[DEBUG] 2016-08-29 17:50:10 :<==    Row: three, 垃圾覆蓋
[DEBUG] 2016-08-29 17:50:10 :<==    Row: four, 裸地覆蓋
[DEBUG] 2016-08-29 17:50:10 :<==    Row: five, 灑水降塵
[DEBUG] 2016-08-29 17:50:10 :<==    Row: six, 車輛沖洗
[DEBUG] 2016-08-29 17:50:10 :<==    Row: seven, 建筑渣土
[DEBUG] 2016-08-29 17:50:10 :<==    Row: eight, 車輛冒裝
[DEBUG] 2016-08-29 17:50:10 :<==    Row: nine, 揚(yáng)塵覆蓋
[DEBUG] 2016-08-29 17:50:10 :<==    Row: ten, 車輛撒漏
[DEBUG] 2016-08-29 17:50:10 :<==    Row: eleven, 車輛黑煙
[DEBUG] 2016-08-29 17:50:10 :<==    Row: twelve, 道路積塵
[{"NAME":"地面沖洗","name":"地面沖洗","code":"one","CODE":"one"},
{"NAME":"邊界圍擋","name":"邊界圍擋","code":"two","CODE":"two"},
{"NAME":"垃圾覆蓋","name":"垃圾覆蓋","code":"three","CODE":"three"},
{"NAME":"裸地覆蓋","name":"裸地覆蓋","code":"four","CODE":"four"},
{"NAME":"灑水降塵","name":"灑水降塵","code":"five","CODE":"five"},
{"NAME":"車輛沖洗","name":"車輛沖洗","code":"six","CODE":"six"},
{"NAME":"建筑渣土","name":"建筑渣土","code":"seven","CODE":"seven"},
{"NAME":"車輛冒裝","name":"車輛冒裝","code":"eight","CODE":"eight"},
{"NAME":"揚(yáng)塵覆蓋","name":"揚(yáng)塵覆蓋","code":"nine","CODE":"nine"},
{"NAME":"車輛撒漏","name":"車輛撒漏","code":"ten","CODE":"ten"},
{"NAME":"車輛黑煙","name":"車輛黑煙","code":"eleven","CODE":"eleven"},
{"NAME":"道路積塵","name":"道路積塵","code":"twelve","CODE":"twelve"}
]

返回的結(jié)果帶有大寫與小寫的key

如果在sql語(yǔ)句中的列名使用大寫會(huì)怎樣呢？自己測(cè)試一下吧！如果大家有任何疑問(wèn)請(qǐng)給我留言，小編會(huì)及時(shí)回復(fù)大家的。在此也非常感謝大家對(duì)億速云網(wǎng)站的支持！

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