Wednesday, September 21, 2016

Button Click event fires when pressing Enter key in different input

I had the same problem and solved it by adding type="button" attribute to the <button> element, by which IE thinks the button as a simple button instead of a submit button (which is default behavior of a <button> element).

Reference:

http://stackoverflow.com/questions/12325066/button-click-event-fires-when-pressing-enter-key-in-different-input-no-forms

A handy tool for writing RESTful API in golang. It enables you to exchange data between client and server through a uniform JSON format

A handy tool for writing RESTful API in golang. It enables you to exchange data between client and server through a uniform JSON format

iojson provides a convenient way to exchange data between your client and server through a uniform JSON format. It helps you to encode data from Go structs to a JSON string and to decode data from a JSON string to Go structs. iojson supports storing Go objects to a slice or to a map, which means you could reference your object either by a slice index or by a map key according to your preference. After populating data from JSON to Go objects, the methods of the objects remained working.

iojson also provides a HTTP middleware function, which works with Alice (a famous middleware chainer).

https://github.com/junhsieh/iojson

Tuesday, September 20, 2016

invalid indirect of typedSlice (type interface {})

invalid indirect of typedSlice (type interface {})

You can't dereference typedSlice, because it's an interface{}. You would have to extract the pointer with a type assertion

realSlice := *typedSlice.(*[]Demo)

cannot range over typedSlice (type interface {})

Again, since typedSlice is an interface{}, you can't range over it. If you want to range over the values you need to use a type assertion, or iterate manually via reflect:

for i := 0; i < o.Elem().Len(); i++ {
    ret = append(ret, o.Elem().Index(i).Interface())
}

Reference:

http://stackoverflow.com/questions/34163174/cant-use-range-on-slice-made-with-reflect-then-passed-json-unmarshal

Friday, September 16, 2016

HttpWebRequest cookie post header Example

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

using System.IO;
using System.Net;
using System.Diagnostics;

namespace HttpWebRequestExample
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        CookieContainer Cookie = null;
        string CSRFtoken = "";

        public MainWindow()
        {
            InitializeComponent();
        }

        private void LoginBtn_Click(object sender, RoutedEventArgs e)
        {
            Cookie = new CookieContainer(); // important

            PerformRequest("POST", "https://erp.local:8443/Login", "{\"ObjArr\":[{\"Username\":\"bot\",\"Password\":\"bot\"}]}");
        }

        private void ItemBtn_Click(object sender, RoutedEventArgs e)
        {
            PerformRequest("GET", "https://erp.local:8443/Item/List", "");
        }

        private void SaveBtn_Click(object sender, RoutedEventArgs e)
        {
            PerformRequest("POST", "https://erp.local:8443/Ship/Save", "{\"Status\":true,\"ErrArr\":[],\"ErrCount\":0,\"ObjArr\":[{\"IDCNShip\":0,\"InvoiceNum\":15,\"ContainerNum\":\"\",\"ETD\":\"2016-09-13\",\"ETA\":\"\",\"IDWarehouse\":0,\"TotalQty\":0,\"IsClosed\":false,\"ShippedDate\":\"\",\"Remark\":\"\",\"Created\":\"\",\"Changed\":\"\",\"CNShipItemWalkerArr\":[{\"LineNum\":0,\"RowNum\":1,\"ItemNum\":\"A0\",\"ItemName\":\"\",\"SizeLong\":\"\",\"ColorShort\":\"\",\"ColorShortZH\":\"\",\"Qty\":0,\"NetWeight\":0,\"GrossWeight\":0,\"UnitPrice\":0,\"Remark\":\"\",\"Created\":\"\",\"Changed\":\"\"}],\"CNShipItemPartArr\":[{\"LineNum\":0,\"BoxLabel\":\"ABC\",\"ItemNum\":\"A1\"}]}],\"Data\":{}}");
        }

        private void PerformRequest(string method, string url, string postData)
        {
            // TODO: this is a temporary remove SSL ceritficate check solution. Please comment out this line in production.
            ServicePointManager.ServerCertificateValidationCallback = new System.Net.Security.RemoteCertificateValidationCallback(AcceptAllCertifications);

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            request.CookieContainer = Cookie; // use the global cookie variable


            byte[] data = Encoding.UTF8.GetBytes(postData);

            request.Method = method;

            request.Headers.Add("X-CSRF-Token", CSRFtoken);

            if (method == "POST")
            {
                request.ContentType = "application/json; charset=utf-8";
                request.ContentLength = data.Length;

                using (Stream stream = request.GetRequestStream())
                {
                    stream.Write(data, 0, data.Length);
                }
            }

            WebResponse response = (HttpWebResponse)request.GetResponse();
            string responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();

            CSRFtoken = response.Headers.Get("X-CSRF-Token");

            Debug.WriteLine("CSRFtoken: " + CSRFtoken);
            Debug.WriteLine(responseString);
        }

        public bool AcceptAllCertifications(object sender, System.Security.Cryptography.X509Certificates.X509Certificate certification, System.Security.Cryptography.X509Certificates.X509Chain chain, System.Net.Security.SslPolicyErrors sslPolicyErrors)
        {
            return true;
        }
    }
}


Reference:

http://csharp-tricks-en.blogspot.ca/2015/03/http-requests-get-or-post-with-cookies.html

Wednesday, September 14, 2016

Convert JSON string to C# object

Convert JSON string to C# object

using System.Windows;

using System.IO;
using System.Text;
using System.Collections.Generic;
using System.Diagnostics;

using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;

namespace WpfApplication4
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void button_Click(object sender, RoutedEventArgs e)
        {
            string str = "{\"Status\":true,\"ErrArr\":[],\"ErrCount\":0,\"ObjArr\":[],\"Data\":{\"Test\":\"Hello\",\"ItemArr\":[{\"IDItem\":111,\"ItemNum\":\"AA01\",\"ItemName\":\"Computer\"},{\"IDItem\":112,\"ItemNum\":\"AA02\",\"ItemName\":\"Desk\"}]}}";

            MemoryStream jsonSource = new MemoryStream(Encoding.UTF8.GetBytes(str));
            var s = new DataContractJsonSerializer(typeof(RootObject));
            var j = (RootObject)s.ReadObject(jsonSource);

            Debug.WriteLine(str);

            Debug.WriteLine(j.Data.Test);

            for (int i = 0; i < j.Data.ItemArr.Count; i++)
            {
                Debug.WriteLine(j.Data.ItemArr[i].IDItem + "; " + j.Data.ItemArr[i].ItemNum + "; " + j.Data.ItemArr[i].ItemName);
            }
        }
    }


    [DataContract]
    public class ItemArr
    {
        [DataMember]
        public int IDItem { get; set; }

        [DataMember]
        public string ItemNum { get; set; }

        [DataMember]
        public string ItemName { get; set; }
    }

    [DataContract]
    public class Data
    {
        [DataMember]
        public string Test { get; set; }

        [DataMember]
        public List<ItemArr> ItemArr { get; set; }
    }

    [DataContract]
    public class RootObject
    {
        [DataMember]
        public bool Status { get; set; }

        [DataMember]
        public List<object> ErrArr { get; set; }

        [DataMember]
        public int ErrCount { get; set; }

        [DataMember]
        public List<object> ObjArr { get; set; }

        [DataMember]
        public Data Data { get; set; }
    }
}

Reference:

http://json2csharp.com/