.Net Core 5下WebAPI FromForm 及FromBody FromQuery使用方式，有图有真相

https://blog.csdn.net/hamunet/article/details/120968882

1. FromForm POST方式
   后端代码：
   [HttpPost("Tel/FromFormTest")]
   public async Task<ActionResult<ResponseMessageWrap>> FromFormTest([FromForm] TelOutPos telOutPos)
   {
   await Task.CompletedTask;
   return new ResponseMessageWrap {Data= telOutPos.agNo };
   }

Js请求：
1、 Content-Type：application/x-www-form-urlencoded
var settings = {
"url": "http://localhost:5003/Tel/FromFormTest",
"method": "POST",
"timeout": 0,
"headers": {
"Content-Type": "application/x-www-form-urlencoded"
},
"data": {
"regId": "123131",
"token": "123123",
"agNo": "123213",
"bindTel": "2222"
}
};

$.ajax(settings).done(function (response) {
console.log(response);
});

2、 Content-Type：multipart/form-data
var form = new FormData();
form.append("regId", "11");
form.append("token", "22");

var settings = {
"url": "http://localhost:5003/Tel/FromFormTest",
"method": "POST",
"timeout": 0,
"processData": false,
"mimeType": "multipart/form-data",
"contentType": false,
"data": form
};

$.ajax(settings).done(function (response) {
console.log(response);
});

3、Content-Type：application/json 对象值传不过去

总结:
1、接口参数为对象:只能key value方式对象传递，后台可以接收到，符合以上3中方式
2、接口参数分别接受，url方式传值不考虑Content-Type 类型都可以接受到的
...FromFormTest1?regId=13&token=1213&agNo=123213&bindTel=123123

后台代码 Dictionary 为key value 集合：
public static async Task<(bool, string)> HttpPostAsyncOptimizeFormUrl(string requestUrl, Dictionary<string, string> dicUrl)
{
try
{
using (HttpClient httpClient = new HttpClient())
{
StringBuilder builder = new StringBuilder();
int i = 0;
foreach (var item in dicUrl)
{
if (i > 0)
builder.Append("&");
builder.AppendFormat("{0}={1}", item.Key, item.Value);
i++;
}
var responseResult = httpClient.PostAsync(requestUrl, new StringContent(builder.ToString(), System.Text.Encoding.UTF8, "application/x-www-form-urlencoded")).Result;
if (responseResult.StatusCode == HttpStatusCode.OK)
{
return (true, await responseResult.Content.ReadAsStringAsync());
}
else
{
return (false, $"接口地址返回错误状态码:{responseResult.StatusCode}");
}

            }
        }

2.FromBody POST方式
后台代码：
[HttpPost("Tel/FromBodyTest")]
public async Task<ActionResult<ResponseMessageWrap>> FromBodyTest([FromBody] TelOutPos telOutPoso)
{
await Task.CompletedTask;
return new ResponseMessageWrap { Data = telOutPoso.agNo };
}
JS:
var settings = {
"url": "http://localhost:5003/Tel/FromBodyTest",
"method": "POST",
"timeout": 0,
"headers": {
"Content-Type": "application/json"
},
"data": JSON.stringify({
"agNo": "1123"
}),
};

$.ajax(settings).done(function (response) {
console.log(response);
});
只能才作用 "Content-Type": "application/json" 这种方式 ，其他方式一律报media type 错误

3.FromQuery
接口参数对象可以接受URL传值，不接受对象传值,GET方式比较符合这种场景，POST当然也可以
FromQueryTest?egId=13&token=1213&agNo=123213&bindTel=123123
后台代码：
[HttpPost("Tel/FromQueryTest")]
public async Task<ActionResult<ResponseMessageWrap>> FromQueryTest([FromQuery] TelOutPos telOutPos)
{
await Task.CompletedTask;
return new ResponseMessageWrap { Data = telOutPos.agNo };
}