客户端使用 fetch 发送 ajax 请求，一直出现401错误，一直认为是服务器端跨域设置问题，后来发现是客户端发送参数不对，

此方式不对，一直返回401

fetch('http://localhost:8080/oauth/token', {  method: 'POST',  model: 'cros',  headers: {    'Accept': 'application/json',    'Content-Type': 'application/json'  },  body: JSON.stringify({    'grant_type': 'password',    'scope': 'select',    'client_id': 'client',    'client_secret': 'client-ppp',    'username': 'zhangsan',    'password': '123456'  })})  .then(function (response) {    console.log('==================1===============')    console.log(response)  })  .catch(function (error) {    console.log('==================2===============')    console.log(error)  })

下面这种可以正常发送参数

let formData = new FormData()// 请求参数 ('key',value)formData.append('grant_type', 'password')formData.append('scope', 'select')formData.append('client_id', 'client')formData.append('client_secret', 'client-ppp')formData.append('username', 'zhangsan')formData.append('password', '123456')fetch('http://localhost:8080/oauth/token', {  method: 'POST',  model: 'cros',  headers: {    'Accept': 'application/json'  },  body: formData})  .then(function (response) {    console.log('==================1===============')    console.log(response)  })  .catch(function (error) {    console.log('==================2===============')    console.log(error)  })