如何从使用interface {}输入的golang map [string]字符串中提取值？
问题描述：
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I have something like this:
x1 := someFunctionWithAnInterfaceReturnValue()
and the underlying type is something like this:
x2 := map[string] string{"hello": "world"}
How would I access value in x1?
Essentially I want the equivalent of this for x1:
var value string = x2["hello"]
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答
Use a type assertion:
x1 := someFunctionWithAnInterfaceReturnValue()
x2, ok := x1.(map[string]string)
if !ok {
// handle unexpected type
}
var value string = x2["hello"]