How to Check for bigest Numeric Value in a Text Box with many Values

Question

i have a text box with many numeric values from deferent columns in a data grid i would like to check from the highest numeric value `in the textbox to the least and change these specific values to "1", "2" or "H1", "H2" etc. until each value is replaced with there ranking from highest to lowest value and save each back to the data grid according to their columns is it possible ? and can some one help me out please.

Help !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! please help !!!!!!!!!!!!!!!!!!!!!! am stalked please help !

Answer 1

Hello @KwebenaAcquah-9104

The following places results into a ListBox for testing only, you would assign these values back to your DataGridView.

DO NOT

Get hung up on the ListBox, it's used simply to validate the code presented works.

Full source

https://github.com/karenpayneoregon/csharp-features/tree/master/ParsingArray

All code has been done in VS2019

A language extension is used (to keep code in the form clean and is reusable) to split the text into a string array. Create a class named ControlExtensions and replace the default content with this.

Class

using System;  
using System.Windows.Forms;  

namespace ParsingArray.Extensions  
{  
    public static class ControlExtensions  
    {  
        public static string[] ToStringArray(this TextBox textBox, char separator = ' ') =>   
            textBox.Text.Split(new[] { separator }, StringSplitOptions.RemoveEmptyEntries);  
    }  
}  

Next create a class named Extensions and place the code below in.

• AllDecimals returns true if all elements in the string array can be converted to decimal (is optional as ToDecimalArray below will handle issues)
• ToDecimalArray converts a string array to decimal, if AllDecimals is not used and an element can not be converted it's value will be 0.
• ItemsFromArray creates a temp container which is used by MaxItem to get the max value

  Class

  namespace ParsingArray.Extensions
  {
  public static class Extensions
  {

      public static decimal[] ToDecimalArray(this string[] sender)  
      {  
  
          var decimalArray = Array.ConvertAll(sender, (input) =>  
          {  
              decimal.TryParse(input, out var decimalValue);  
              return decimalValue;  
          });  
  
          return decimalArray;  
  
      }  
  
      public static List<Item> ItemsFromArray(this decimal[] sender) =>   
          sender.Select((value, Index) => new Item() {Index = Index, Value = value}).ToList();  
  
      public static bool AllDecimals(this string[] sender) =>   
          sender.All(item => decimal.TryParse(item, out var test));  
  
      public static Item MaxItem(this List<Item> sender) =>   
          sender.OrderByDescending(x => x.Value).FirstOrDefault();  
  }  
  

  }

Form code

namespace ParsingArray  
{  
    public partial class Form1 : Form  
    {  
        public Form1()  
        {  
            InitializeComponent();  
        }  

        private void button1_Click(object sender, EventArgs e)  
        {  

            listBox1.Items.Clear();  

            var stringValues = textBox1.ToStringArray();  

            if (!stringValues.AllDecimals()) return;  
            var result = stringValues.ToDecimalArray().ItemsFromArray().MaxItem();  
            if (result != null) stringValues[result.Index] = "H";  

            listBox1.Items.AddRange(stringValues);  

        }  
    }  
}  

Update

This will rank each item from max to lowest.

private void button2_Click(object sender, EventArgs e)  
{  
    var stringValues = textBox1.ToStringArray();  

    var itemList = stringValues  
        .ToDecimalArray()  
        .ItemsFromArray()  
        .OrderByDescending(item => item.Value)  
        .ToList();  

    for (int index = itemList.Count - 1; index >= 0; --index)  
    {  
        itemList[index].Text = $"H{index + 1}";  
    }  

    foreach (var item in itemList)  
    {  
        Debug.WriteLine($"{item.Text}\t{item.Value}");  
    }  
}  

Output

H1  1126.90  
H2  909.50  
H3  467.20  
H4  400.20  
H5  397.50  
H6  387.60  
H7  371.50  
H8  366.10  
H9  356.90  
H10 345.60  
H11 335.00  
H12 289.40  
H13 283.40  
H14 87.00  
H15 77.00  
H16 76.00  
H17 76.00  
H18 54.00  
H19 45.00  
H20 34.00  
H21 23.00  
H22 8.00  
H23 4.00  
H24 4.00  
H25 3.00  
H26 3.00  

Answer 2

First, split the text into its contained values. Then convert them to numeric. Then calculate the max. Then you can concatenate them back if you wish, after changing the one that you found:

string[] parts = textBox1.Text.Split(new char[]{' '}, StringSplitOptions.IgnoreEmptyEntries);
double[] numbers = parts.Select(p => double.Parse(p)).ToArray();
double maximum = numbers.Max();
int position = Array.IndexOf(numbers, maximum);
parts[position] = "H";
textBox1.Text = string.Join(" ", parts);

Of course, this allows plenty of refinements, such as using a TryParse instead of double.Parse to avoid errors if one of the elements does not have the right format, or using a loop to find the index at the same time as the maximum, etc.