使用WPF中的ivalueconverter将数据从字符串转换为复选框 [英] Convert data from string to checkbox with ivalueconverter in WPF

问题描述

我的应用有问题。我用WPF构建了一个应用程序。我有一个数据是从DB导入的observablecollection，这个数据的一部分（一个属性）是字符串，我想将这个数据绑定到复选框这个字符串数据看起来像

（abc_abcd / abc_abcd / abc_abcd .....）

每个abc_abcd它应该链接到一个Checkbox（这个字符串是用户授权，它作为一个字符串存储在数据库中但是当我想将它绑定到复选框时我应该溢出然后将它与每个Checkbox的静态值进行比较，以了解是否应该检查tjis Checkbox）。我知道我应该使用ivalueconverter，但我不知道如何制作它。任何解决方案请......

  class 运算符
 {
  public   string  operatorname { get ;  set ; } 
  public   string  operatorpassword { get ;  set ; } 
  public   string  authorization { get ;  set ; } 
  public   Boolean  renew_password { get ;  set ; } 
  public   int  interval_of_change { get ;  set ; } 
  public   int  password_min_length { get ;  set ; } 
  public  DateTime last_change { get ;  set ; } 
} 

  class  Databasecon 
 {
 
 
 
 
  //  数据库的第一次绑定 
  public  ObservableCollection< Operator>运算符{ get ;  private   set ; } 
 
 
  public  Databasecon（）
 {
 
  this  .operators =  new  ObservableCollection< Operator>（）; 
 
} 
 
  public   void  Datacon（< span class =code-keyword> string  conn）
 {
 MySqlConnection con =  null ; 
 MySqlCommand com =  null ; 
 MySqlDataReader myreader =  null ; 
  int  columnOrdinaloperatorname = -1; 
  int  columnOrdinalauthorisation = -1; 
 
 
 con =  new  MySqlConnection（conn）; 
 尝试 
 {
 如果（com ==  null ）
 {
 com =  new  MySqlCommand（  SELECT * FROM运算符，con）; 
 com.Connection.Open（）; 
 
 myreader = com.ExecuteReader（）; 
 columnOrdinaloperatorname = myreader.GetOrdinal（  operator_name）; 
 columnOrdinalauthorisation = myreader.GetOrdinal（  authorization）; 
 
  while （myreader.Read（））
 {
 
  this  .operators.Add（ new  Operator（）{
 operatorname = myreader.GetString（columnOrdinaloperatorname）.ToString（），
  //   DB中的授权可以为空 
 authorization =（columnOrdinalauthorisation >  =  0 ）？（myreader.IsDBNull（columnOrdinalauthorisation）？ string  .Empty：myreader.GetString（columnOrdinalauthorisation））： string  .Empty 
}）; 
 
} 
 
 
 
} 
 
 
} 
 
 
  catch （MySqlException ex）
 {
 MessageBox.Show（ex.ToString（））; 
 
 
} 
 最后 
 {
 
  if （myreader！=  null ）
 myreader.Close（）; 
 
  if （com！=  null ）
 {
  if （com.Connection！=  null ）
 com.Connection.Close（） ; 
} 
 
} 
} 
 
} 
 
 pre> 
 
 
< pre lang =   c＃ >  < /   
  < span class =code-keyword> 
   
   
   
   
   class     collect    ：    INotifyPropertyChanged   
   
           {  
   
                   string     myconn     =  < span class =code-keyword>    SERVER = localhost; PORT = 3306; UID = TestUser; PASSWORD = TestUser; DATABASE = heitel_db_v011 ;   
   
                   private     Databasecon     databasecon     =     null;   
   
                   public     event     PropertyChangedEventHandler     PropertyChanged;   
   
                   public     ICommand     Bindingcommand     {    get;     set;    }   
   
   
   
   
   
                   public  < span class =code-keyword>   ObservableCollection<运算符 > 运算符
 {
  get  
 {
  if （此 .databasecon.operators！=  null ）
 
 {
 返回 < span class =code-keyword> this  .databasecon.operators; 
 
 
} 
 
  else  
 {
 
 
  return   null ; 
} 
 
 
} 
  set  
 {
 此 .operators =  value ; RaisePropertyChanged（  operator）; 
} 
 
} 
 
  private   void  RaisePropertyChanged（ string  propertyName）
 {
  var  handler = 此 .PropertyChanged; 
  if （handler！=  null ）
 {
 handler（  this ， new  PropertyChangedEventArgs（propertyName））; 
} 
} 
 
 
  public  collect（）
 {
 < span class =code-keyword> this  .databasecon =  new  Databasecon（）; 
 Bindingcommand =  new  Relaycommands（（）= >  databasecon.Datacon（myconn））; 
 
} 
 
 
} 

 类 Relaycommands：ICommand 
 {
  public   event  EventHandler CanExecuteChanged; 
  private  Action _command; 
 
 
  public  Relaycommands（Action command）
 {
 _command = command; 
 
} 
  public   bool  CanExecute（ object 参数）
 {
  return   true ; 
} 
 
  public   void 执行（ object 参数）
 {
  if （_command！=  null ）
 _command（）; 
} 
} 

我的尝试：



我试着写转换器，但我不能。我不知道什么时候应该将字符串数据溢出到单词并将其保存在数组

解决方案

你好，



这应该有所帮助：



如何：使用String.Split解析字符串（C＃编程指南） [ ^ ]



和



http://www.wpf-tutorial.com/data-binding/value-conversion-with-ivalueconverter / [ ^

I have a Problem with my app. I build an app with WPF. I have a data it is imported from DB with observablecollection, part of this data (one properity) is string and I want to bind this data to checkboxes this string data Looks like

(abc_abcd/abc_abcd/abc_abcd.....)

every abc_abcd it should be linked to one Checkbox( this string is user authorisations and it stored in the data base as one string but when i want to bind it to checkboxes i should spilt it and then compare it with static value for every Checkbox to know if tjis Checkbox should be checked or not ). I know that I should use ivalueconverter but I don't have an idea how to make it. any Solution please......

class Operator
    {
        public string operatorname { get ; set; }
        public string  operatorpassword { get; set; }
        public string authorisation { get; set; } 
        public Boolean renew_password { get; set; }
        public int interval_of_change { get; set; }
        public int password_min_length { get; set; }
        public DateTime last_change { get; set; }
    }

 class Databasecon  
    {
       

       

        // First Binding for the Database
       public ObservableCollection<Operator> operators { get; private set; }


        public Databasecon()
        {

            this.operators = new ObservableCollection<Operator>();
            
        }
       
       public void Datacon(string conn)
        {
            MySqlConnection con = null;
            MySqlCommand com = null;
            MySqlDataReader myreader = null;
            int columnOrdinaloperatorname = -1;
            int columnOrdinalauthorisation = -1;


            con = new MySqlConnection(conn);
            try
            {
                if (com == null)
                {
                    com = new MySqlCommand("SELECT * FROM operators", con);
                    com.Connection.Open();

                    myreader = com.ExecuteReader();
                    columnOrdinaloperatorname = myreader.GetOrdinal("operator_name");
                    columnOrdinalauthorisation = myreader.GetOrdinal("authorisation");

                    while (myreader.Read())
                    {

                        this.operators.Add(new Operator() {
                            operatorname = myreader.GetString(columnOrdinaloperatorname).ToString(),
                             // authorisation can be Null in DB
                            authorisation = (columnOrdinalauthorisation >= 0) ? (myreader.IsDBNull(columnOrdinalauthorisation) ? string.Empty : myreader.GetString(columnOrdinalauthorisation)) : string.Empty
                        }); 

                    }

                    
                    
                }


            }


            catch (MySqlException ex)
            {
                MessageBox.Show(ex.ToString());
               

            }
            finally
            {

                if (myreader != null)
                    myreader.Close();

                if (com != null)
                {
                    if (com.Connection != null)
                        com.Connection.Close();
                }
            
            }
    }
   
}

pre>


<pre lang="c#"></





class collect : INotifyPropertyChanged

    {

        string myconn = "SERVER=localhost;PORT=3306;UID=TestUser;PASSWORD=TestUser;DATABASE=heitel_db_v011";

        private Databasecon databasecon = null;

        public event PropertyChangedEventHandler PropertyChanged;

        public ICommand Bindingcommand { get; set; }





        public ObservableCollection<Operator> operators
        {
            get
            {
                if (this.databasecon.operators != null)
                   
                {
                       return this.databasecon.operators;
                   
                      
                }

                else
                {


                    return null;
                }
                   

            }
            set
            {
                this.operators = value; RaisePropertyChanged("operators");
            }

        }

        private void RaisePropertyChanged(string propertyName)
        {
            var handler = this.PropertyChanged;
            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs(propertyName));
            }
        }


        public collect()
        { 
            this.databasecon = new Databasecon();
            Bindingcommand = new Relaycommands(() => databasecon.Datacon(myconn));
           
        }


    }

class Relaycommands : ICommand
    {
        public event EventHandler CanExecuteChanged;
        private Action _command;


        public Relaycommands(Action command)
        {
            _command = command;

        }
        public bool CanExecute(object parameter)
        {
            return true;
        }

        public void Execute(object parameter)
        {
            if (_command != null)
                _command();
        }
    }

What I have tried:

I try to write the converter but I couldn't. I don't know when I should Spill the string data to words and save it in an Array

解决方案

Hello,

this should help:

How to: Parse Strings Using String.Split (C# Programming Guide)[^]

and

http://www.wpf-tutorial.com/data-binding/value-conversion-with-ivalueconverter/[^]

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