如何使用golang将xml消息解组到结构中

how to decode this xml

<?xml version="1.0" encoding="UTF-8"?>
<LocationConstraint>oss-cn-hangzhou</LocationConstraint>

my code is like this:

type BucketLocation struct {
    LocationConstraint string `xml:"LocationConstraint"`
}
v := &BucketLocation{}
xml.Unmarshal(xml_content, v)

but it does not work.

The definition of your struct implies the following XML format which doesn't match what you're providing:

<BucketLocation>
    <LocationConstraint>oss-cn-hangzhou</LocationConstraint>
</BucketLocation>

To read the example XML that you've given you would do something this:

var v string
xml.Unmarshal(xml_content, &v)