1.
map<String, Schema.SObjectType> gd = Schema.getGlobalDescribe();
map的key是 object api name
比如 “Account”
可以: gd.containsKey(“Account”) 去判断一个object里有没有那个field
2.
map<String, Schema.SObjectType> gd = Schema.getGlobalDescribe();
Schema.SObjectType sot = gd.get(objApi);
Schema.DescribeSObjectResult sobjr = sot.getDescribe();
3.
map<String, Schema.SObjectType> gd = Schema.getGlobalDescribe();
Schema.DescribeSObjectResult sobjr = gd.get(objApi).getDescribe();
objApi 是 object api name