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javascriptasp.netajaxjsonwebmethod

Javascript values to WebMethod


I am trying to simply pass some values from Javascript into my codebehind for processing. I just want to pass a Number and Message to the WebMethod but get different errors based on whatever thing I change.

JS:

function SendMessage() {
var number = document.getElementById("number").value;
var message = document.getElementById("message").value;

var msg = {
    "Number": number,
    "Message": message
};

$.ajax({
    type: "POST",
    url: "Default.aspx/SendMessage",
    data: JSON.stringify(msg),
    contentType: "application/json; charset=utf-8",
    dataType: "json",
    success: function (msg) {
        alert("Message sent");
    },
    error: function (msg) {
        alert("Message call failed");
    }
});
}

In my codebehind I have a WebMethod defined and also a Message class to hold my message

[WebMethod]
public static void SendMessage(string message)
{
    //Create a  TMessage and deserialize to it

}

Message:

public class TMessage
{
    public string Number { get; set; }
    public string Message { get; set; }
}

My understanding is that I am receiving JSON and should deserialize it to a Message type. However I have a breakpoint in the SendMessage method and it never gets hit, the error being returned is: Message=Invalid web service call, missing value for parameter: 'message'.

From some playing around earlier, I was able to get the breakpoint hit by changing the parameter from string to object (and some changes to the data: value in the Ajax call), but then it seemed I was receiving a Dictionary and I couldn't cast it to TMessage.

Thanks for any suggestions.


Solution

  • If you clearly look at webmethod , it has only one param i.e. message .

    You need to pass this to ajax call. - var params = "{'message':'" + message + "'}";

    Helpful link - Send JSON to webmethod?

    function SendMessage() {
    
    var number = document.getElementById("phonenumber").value;
    var message = document.getElementById("message").value;
    
    var params = "{'message':'" + message + "', 'number':'" + number + "'}";
    $.ajax({
        type: "POST",
        url: "Default.aspx/SendMessage",
        data: params,
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        success: function (msg) {
            alert("Message sent");
        },
        error: function (msg) {
            alert("Message call failed");
        }
    });
    }