Call C# method from JavaScript with parameter

Question

I want to call a C# method with parameter from JavaScript. It is possible, if I remove the parameter s of the method <% showDetail(); %> <% showDetail(); %>

function showDetail(kurz)
        {
            String s = kurz.toString();
            <% showDetail(s); %>;
        }

C# methods to test:

public void showDetail(String s)
        {
            Label_Test.Text = s.ToString();
        }
public void showDetail()
        {
            Label_Test.Text = "";
        }

It works fine without parameter but with s variable I get a compiler error:

CS0103: The name 's' does not exist in the current context

I have tried

showDetail(Object s){....}

and also

showDetail(String s){....}

but it does not work.

Answer 1

Create a web method. That's an easy and neat way of calling c# methods from Javascript. You can call that method using jQuery Ajax. See the below example for a webMethod.

[WebMethod]
public static string RegisterUser(string s)
{
    //do your stuff
    return stringResult;
}

and then call this method using jQuery ajax. You can pass parameters also. like given below

function showDetail(kurz) { 
String sParam = kurz.toString(); 
    $.ajax({ 
    type: "POST", 
    url: "PageName.aspx/MethodName", 
    data: "{s:sParam}", // passing the parameter 
    contentType: "application/json; charset=utf-8", 
    dataType: "json", 
    success: function(retValue) {
        // Do something with the return value from.Net method
        } 
    }); 
} 

Answer 2

Use Hidden field to pass the value(set the value using javascript.). And call the javscript function with out parameter.. That value u can get it from the hidden field

Answer 3

You can achieve this by using WebMethods

First of all create a webmethod.

    [WebMethod]
public string MethodName(string Parameter)
{
string msg=string.Empty;
//Your Code
return msg;
}

And in Java Script call that functions as

WebService.MethodName(Parameter,onSuccess,Error) // Here Webservice is the name of your asmx file

function onSuccess(result)
{
//Your code
}

function Error()
{
alert("Error");
}

Answer 4

the solution provide by Varun Paul is the one I have used and it works as long you correct the following error: data: "{s:sParam}",

It should be written as: data: { s:sParam },

data is used to pass parameters to the C# method. Hope it helps. Thanks,

Answer 5

Its possible to interact c# application with javascrip t, use jint.dll for that

Jint - Javascript Interpreter for .NET

For Example

Following are the java script functions

function reverse(my_str)  
{ 
    var sb = new jintTestApplication.Test();//jintTestApplication is the namespace name
    return sb.Test1(reverse2(my_str) );
} 

function reverse2(my_str)  
{    
 var comStr="";  
    var result="";  
    var i=my_str.length;  

    i=i-1;  
     for (var x = i; x >=0; x--)  
      {  
        result= my_str.charAt(x);  
        comStr+=result;  
       }  
   return comStr; 
} 

so in this case you have to create the object of your class inside the javascript and is possible to call ac# method

            JintEngine engine = new JintEngine();
            engine.Run(ReadJavaScript());
            Console.WriteLine(engine.Run("reverse('Foooooo');"));

   public static  string ReadJavaScript()
   {
    string allines = File.ReadAllText(@"[path]\test.js");
   }



public void Test1(string message)
{
MessageBox.show(message);
}