$.ajax({
    url: "[url of page]",
    type: "POST",
    data: {saluto: true},
    dataType: 'text',
    success: function (response) {
        alert("successful" + response);
    },
    error: function () {
        alert("error");
    }
});

[HttpPost("Test")]
public async Task<string> testHelloWorld(bool saluto)
{

    try
    {
        string testString = "Funziona";
        Console.Write(testString + ": " + saluto + "n");
        return testString;
    }
    catch (Exception ex)
    {
        Log.Error("API(CallToXML) - Exception", ex);
        return null;
    }
}

public async Task<string> testHelloWorld([FromBody]bool saluto)