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JavaScript findIndex不适用于第一个对象_Javascript_Arrays_Indexing_Find - Fatal编程技术网

JavaScript findIndex不适用于第一个对象

JavaScript findIndex不适用于第一个对象,javascript,arrays,indexing,find,Javascript,Arrays,Indexing,Find,当我使用第一个对象“vpnkey value”搜索vpnkey时,它返回-1,但预期结果为0 var data=[{"vpnkey":"CUSTOMER_NAME","validation":"ALPHANUMERIC"}, {"vpnkey":"VRF","validation":"VRF_CHECK"}, {"vpnkey":"MOBILE_ADDRESS_SUMMARIZED_RANGE","validation":"IP_MASK"}, {"vpnkey":"APN_MOBILE_RAN

当我使用第一个对象“vpnkey value”搜索vpnkey时,它返回-1,但预期结果为0

var data=[{"vpnkey":"CUSTOMER_NAME","validation":"ALPHANUMERIC"},
{"vpnkey":"VRF","validation":"VRF_CHECK"},
{"vpnkey":"MOBILE_ADDRESS_SUMMARIZED_RANGE","validation":"IP_MASK"},
{"vpnkey":"APN_MOBILE_RANGE","validation":"IP_MASK"},
{"vpnkey":"FIXED_IP_LOOPBACK_TRACK_ID","validation":"NUMERIC"},
{"vpnkey":"CUSTOMER_BGP_REMOTE_AS","validation":"NUMERIC"},
{"vpnkey":"testing_purpass1","validation":"IP_ADDRESS"},
{"vpnkey":"testing_purpass2","validation":"IP_ADDRESS"}]
当我基于vpnkey进行搜索时,第一个对象“vpnkey值”会给出适当的索引值

this.vpnKeys["Commonkeys"].findIndex(function(item, i){
   if(item.vpnkey === "CUSTOMER_NAME") return i
});

findIndex
将返回数组中满足条件的第一个元素的索引。因此,您可以
return item.vpnkey==“CUSTOMER\u NAME”

var数据=[{
“vpnkey”:“客户名称”,
“验证”:“字母数字”
}, {
“vpnkey”:“VRF”,
“验证”:“VRF_检查”
}, {
“vpnkey”:“移动地址范围”,
“验证”:“IP_掩码”
}, {
“vpnkey”:“APN_移动_范围”,
“验证”:“IP_掩码”
}, {
“vpnkey”:“固定IP\U环回\U轨道\U ID”,
“验证”:“数字”
}, {
“vpnkey”:“客户\u BGP\u远程\u AS”,
“验证”:“数字”
}, {
“vpnkey”:“测试目的1”,
“验证”:“IP_地址”
}, {
“vpnkey”:“测试目的2”,
“验证”:“IP_地址”
}]
常数x=data.findIndex(函数(项,i){
return item.vpnkey==“客户名称”
});

console.log(x)
findByIndex
方法返回满足给定数组中提供的测试函数(条件)的索引,这就是该方法的全部用途

关键是理解返回函数的值,这是满足条件的索引,下面是一个小示例:

var-friendPets=['Dog'、'Cat'、'Turtle'];
var someFriend=friendPets.findIndex(函数(pet)){
返回宠物=='海龟';
});
var otherFriend=friendPets.findIndex(函数(pet)){
返回宠物=='Trex';
});
console.log(someFriend)//2因为一个朋友在阵法的第2位有一只乌龟
console.log(其他朋友);//-1由于Trex已灭绝(在阵列中未找到)
this.vpnKeys["Commonkeys"].findIndex(function(item, i){
   if(item.vpnkey === "VRF") return i
});