AJAX 发布数据到达 ASP.NET Core 2.1.1 控制器时为空

Question

I have a problem posting a value from java-script in my razor page to a controller. - the value received is always null.

I have seen similar questions being asked, but have not been able to find the right solution to the problem.

I get to a break point in the controller, (so the routing is okay) but the parameter value passed is always null, and not being the sharpest in java-script, I would like some tips from you folks.

I basically have the java-script below:

 var clickButton = function (buttonId) {
        $.ajax({
            type: "POST",
            async: false,
            cache: false,
            crossDomain: false,
            contentType: "application/json; charset=utf-8",
            url: "v1/buttons",
            dataType: "json",
            data: '{ buttonId:'+JSON.stringify( "buttonId" ) + '}',
            success: function (result) {
                //console.log("clickButton OK => " + result);
            }, //success: function (result) {
            timeout: 500 // 0.5 sec.
        }); //$.ajax({
    }//var clickButton = function(buttonNo) {

and the C# controller code below too:

[Route( "v1/[controller]" )]
public class ButtonsController : Controller
{
 ...
  [HttpPost]
  public IActionResult OnButtonClicked( string buttonId )
  {
    // buttonId = null !!!
   ...

I have a similar problem getting a boolean value across to another controller. where the bool is always false.. ie the default value. I am wondering if it is a security issue, with not allowing the post to contain data, when the user is unauthorized...

Answer 1

The problem was in the JSON, and I got the value through with this minor change, but it was hiding well.

 var clickButton = function (buttonNo) {
     console.log("clicked: " + buttonNo);
     $.ajax({
         type: "POST",
         url: "v1/buttons/",
         dataType: "json",
         data: { "buttonId": buttonNo }, // < === this is where the problem was !!
         success: function (result) {
         }, //success: function (result) {
      }); //$.ajax({
    }//var clickButton = function(buttonNo) {

I've changed the controller to receive a string to id the button. And it now looks like this:

[Route( "v1/[controller]" )]
public class ButtonsController : Controller
{
  ...
  [HttpPost]
  public IActionResult PostButtonClick( string buttonId ) {
    // buttonId now has a value !!!
  }
}