("NetworkError: 401 Unauthorized) Calling code behind method from JavaScript

Question

我正在尝试从 JS 调用代码隐藏方法 但它给了我这个错误

NetworkError: 401 Unauthorized

这是方法背后的代码

[System.Web.Services.WebMethod]
public string ExtractToPDF(string FSID)
{
   return FSID;
}

这是 JS 函数

 function extractFile(FSID) {
        $.ajax({
            type: "POST",
            contentType: "application/json; charset=utf-8",
            url: "Update.aspx/ExtractToPDF",
            data: "{"+FSID+"}",
            dataType: "json",
            success: function(data) {
                alert(data)
            },
            error: function(result) {
                alert("Error");
            }
        });
    }

这是回复

{
"Message": "An error occurred during the processing of the request",
"StackTrace": "",
"ExceptionType": ""
}

Answer 1

方法背后的代码需要是静态的

简单的解决方案：

[System.Web.Services.WebMethod]
public static string ExtractToPDF(string FSID)
{
    return FSID;
}