Relevant knowledge under WinForm

1. String comparison equals, Constant before , Variables come later , In this way, it is not necessary to judge whether the variable is empty first

2. dataTable.copy();// Copy structure and data
    dataTable.clone();// Just copy the structure , Don't copy data

3.BeginInit and EndInit

If a component implements ISupportInitialize Interface , Then the designer will generate BeginInit and EndInit.
The most important function of this interface is , The multiple BeginInit and EndInit The order between them is treated as a hammer deal .
Suppose a class , There are maximum and current values , The current value cannot be greater than the maximum value .
The problem is that the designer can hardly guarantee to set the maximum value first , Then set the current value （ Other controls may also be set My example ）.
If it supports ISupportInitialize, that My Class understands that it is still in the initialization stage , Don't bother to check for errors , Don't bother to deal with every change

4. User controls and custom components and forms

User control ： Custom reusable components , Easy to create , If the control has a large number of static layouts , User controls are preferred , Cannot be added to toolbox

Custom components ： It is also a reusable component , Create with code , Difficult to create userControl class , Easier to use , Can be added to the toolbox , Compiled into dll

forms ： Containers for both

5.DataTable and DataView Interconversion

    DataView view = DataTable.DefaultView;
    view.RowFilter = "BANKNO='5002'";//DataView Query criteria
    view.Sort = "CHANNELID,NETPOINT,BANKNO,PAYWAY";//DataView  Sort

   DataTable.DataSource = view.Table;

6. Add a bullet box
      MessageBox.Show(" Current working day TA Liquidation has been completed ", " System prompt ", MessageBoxButtons.OK, MessageBoxIcon.Information);

7. Add selection pop-up

                 DialogResult dateMessage = XtraMessageBox.Show(string.Format(" Header bill generation date :{0} And the current trading day :{1} atypism , Continue reconciliation ?", "1", "1"), " Tips ", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
                        if (dateMessage == DialogResult.No)
                        {
                            return;
                        }
8. Timing function
      System.Diagnostics.Stopwatch singleStopwatch = new System.Diagnostics.Stopwatch();
      singleStopwatch.Reset();singleStopwatch.Start();  

      singleStopwatch.Stop();

      singleStopwatch.Elapsed.TotalSeconds;

9. Operation folder

 // Determine if the directory exists , Create if it does not exist
                        if (!Directory.Exists(localDir))
                        {
                            Directory.CreateDirectory(localDir);
                        }

Directory.GetFiles(localDir)// Get all files in the file directory

10. Read line by line txt file

while (!file.EndOfStream)
                {

                    var _row = file.ReadLine();
                    if (_rowNum == 1)
                    {
                        _row = System.Text.RegularExpressions.Regex.Replace(_row, @"\s+", "|");  // Convert spaces into | In order to intercept the string later , The replacement character must not appear in the original string
                        tradeNum = _row.Split('|')[0] is null ? ":0" : _row.Split('|')[0];// Intercepts the total number of transactions
                        tradeNum = tradeNum.Split(':')[1] is null ? "0" : tradeNum.Split(':')[1];
                        log.Info(string.Format(" The total number of transactions in the quick money reconciliation file ：{0}", tradeNum))         

                    }                                 
                }