JSON data html parameter

为什么JSON不能与html文本一起工作(var text_html = ' <p></p><t></t> ';)但这将工作正确(var text_html = 'example';)

不工作

var text_html = JSON.parse('<p></p><t></t>'); 

问题:

    function Save() {
        var text_html = '<p></p><t></t>'; 
        $.ajax({
            url: '@Url.Action("DodajTematSave", "StronaGlowna")',
            dataType: "json",
            data: {
                My_Text: text_html
            },
            type: "POST",
            async: false,
            error: function () {
            },
            success: function (data) {
                if (data.Success) {
                    alert('success');
                }
            }
        });
    }
</script>
public JsonResult DodajTematSave(string My_Text)
        {
            return Json(new { Success = true});
        }

也不行

var dom_string = '<div>xxx<div>yyy</div></div>';
    var text_html = dom_string.innerText();

也不行

<script type="text/javascript">
    function Save() {
        var Temat_controll = $('#Temat').val();
        var Streszczenie_controll = $.parseJSON('<p></p><t></t>'); 
        var PelnyOpis_controll = $('#PelnyOpis').text();
         $.ajaxSetup({
             contentType: "application/json; charset=utf-8",
             dataType: "json"
         });
        $.ajax({
            url: '@Url.Action("DodajTematSave", "StronaGlowna")',
            dataType: "json",
            data: {
                Temat: Temat_controll,
                Streszczenie: Streszczenie_controll,
                PelnyOpis: PelnyOpis_controll
            },
            type: "POST",
            async: false,
            error: function () {
            },
            success: function (data) {
                if (data.Success) {
                    alert('success');
                }
            }
        });
    }
</script>