Json 如何在颤振中过滤贴图?
我有一个json文件,如下所示。当用户选择金额和到期日时,我需要显示到期日值 示例:如果用户选择金额=500,到期日=2400万。我需要显示数字6 如何在颤振中过滤贴图 以下是我迄今为止所做的: 我的json文件:Json 如何在颤振中过滤贴图?,json,filter,dart,flutter,Json,Filter,Dart,Flutter,我有一个json文件,如下所示。当用户选择金额和到期日时,我需要显示到期日值 示例:如果用户选择金额=500,到期日=2400万。我需要显示数字6 如何在颤振中过滤贴图 以下是我迄今为止所做的: 我的json文件: { “AMOUNT”:[ { "500":{ “MATURITY":[ { "12M”:”4” },
{
“AMOUNT”:[
{
"500":{
“MATURITY":[
{
"12M”:”4”
},
{
"24M”:”6”
},
{
"36M”:”8”
},
{
"48M”:”10”
},
{
"60M”:”12”
}
]
},
“1000":{
“MATURITY":[
{
"12M”:”8”
},
{
"24M”:”12”
},
{
"36M”:”16”
},
{
"48M”:”20”
},
{
"60M”:”24”
}
]
}
}
]
}
// Test part trying to load json into basic map...
String jsonFastMaturity = await rootBundle.loadString("assets/myfile.json");
Map _mapFastMaturity = jsonDecode(jsonFastMaturity);
List _tmpFastMaturity = _mapFastMaturity[“AMOUNT”];
Json加载:
{
“AMOUNT”:[
{
"500":{
“MATURITY":[
{
"12M”:”4”
},
{
"24M”:”6”
},
{
"36M”:”8”
},
{
"48M”:”10”
},
{
"60M”:”12”
}
]
},
“1000":{
“MATURITY":[
{
"12M”:”8”
},
{
"24M”:”12”
},
{
"36M”:”16”
},
{
"48M”:”20”
},
{
"60M”:”24”
}
]
}
}
]
}
// Test part trying to load json into basic map...
String jsonFastMaturity = await rootBundle.loadString("assets/myfile.json");
Map _mapFastMaturity = jsonDecode(jsonFastMaturity);
List _tmpFastMaturity = _mapFastMaturity[“AMOUNT”];
这应该行得通
final amount = "500";
final maturity = "24M";
_mapFastMaturity["AMOUNT"][0][amount]["MATURITY"].singleWhere((m) => m.containsKey(maturity))[maturity]
如果您遇到错误,这将有助于调试。这里哪一行有错误
final a = _mapFastMaturity["AMOUNT"];
final b = a[0];
final c = b[amount];
final d = c["MATURITY"];
final e = d.singleWhere((m) => m.containsKey(maturity));
final f = e[maturity];
没用。对null调用了方法“[]”。我编辑了[_amount][“MATURITY”]来创建一个调试代码,您能看到哪一行失败了吗?