Question

我在asp.net中有PageMethods的问题，我有一个调用JavaScript函数的按钮，这个函数有一个PageMethod，它从我的c＃codebehind中的方法返回一个值。但是当我点击按钮时，PageMethod不返回任何内容，返回值直到我第二次单击该按钮。

 <%@ Page Language="C#" AutoEventWireup="true" EnableEventValidation="true"   CodeFile="Default.aspx.cs" Inherits="_Default" %>

这是我的asp.net代码：

    <form id="form1" runat="server">
   <asp:ScriptManager ID="ScriptManager1" EnablePageMethods="true" EnablePartialRendering="true" runat="server" />    
    <asp:Button ID="btnViaje" runat="server" Text="Viajes"  OnClientClick="CargarViajes(); return false;" />
    <asp:Button ID="btnRuta" runat="server" Text="Ruta" OnClientClick="CargarRuta(); return false;" />
    <div id="map_canvas" style="width:900px;display:block;float:left"></div>
    <p id="co" style="display:block; float:left">Estadia: </p>   
    <input type="hidden" value="" id="SendA" name="SendA" />
   <button onclick="rastreo()" style="width:50px;height:20px;">rastreo</button>
</form>

当我点击按钮btnViaje调用javascript函数但响应没有返回任何内容，直到我再次点击按钮：

 function CargarViajes() {

        PageMethods.ConvertDataTabletoString(function (response) {
            camiones = eval("(function(){return " + response + ";})()"
                );
        });
    }

这是我的c＃方法：

[WebMethod]
    public static string ConvertDataTabletoString()
    {
        DataTable dt = new DataTable();
        using (SqlConnection con = new SqlConnection("Data Source=PROYECTOLALAE2\\SQLEXPRESS;Initial Catalog=DB_LALA_Rastreo_Rastreo;Integrated Security=true"))
        {
            using (SqlCommand cmd = new SqlCommand("SELECT Id_Viaje=idviaje, LatV=latitud, LonV=longitud, Velocidad=velocidad, In1=entrada1_dig, In2=entrada2_dig, AI1=entrada1_analoga, AI2=entrada2_analoga FROM Tb_Viaje_Coordenada", con))
            {
                con.Open();
                SqlDataAdapter da = new SqlDataAdapter(cmd);
                da.Fill(dt);
                System.Web.Script.Serialization.JavaScriptSerializer serializer = new System.Web.Script.Serialization.JavaScriptSerializer();
                List<Dictionary<string, object>> rows = new List<Dictionary<string, object>>();
                Dictionary<string, object> row;
                foreach (DataRow dr in dt.Rows)
                {
                    row = new Dictionary<string, object>();
                    foreach (DataColumn col in dt.Columns)
                    {
                        row.Add(col.ColumnName, dr[col]);
                    }
                    rows.Add(row);
                }
                return serializer.Serialize(rows);
            }
        }
    }

Answer 1

像这样更新您的JavaScript：

function CargarViajes() {
    PageMethods.ConvertDataTabletoString(OnSucceeded); 
}

function OnSucceeded(result, userContext, methodName) 
{          
    if (methodName == "ConvertDataTabletoString") 
    { 
        // Now do whatever you like with results from ConvertDataTabletoString
        return result;
    } 
}

带有pagemethods的asp.net不起作用

1 个答案: