c# - 如何在对象上声明没有名称的 Get/Set 方法？

Question

我正在尝试创建一个支持以下内容的 C# 类...

// Sets a string: sg(1,1) = "value";
// Gets a string: "value" = sg(1,1);
// sg.ExportToExcel(ClosedXML.Excel.Worksheet, row = 1, col = 1) // Write sg to Excel for worksheet X, starting at row or row/col

Example Usage:

StringGrid sg = new StringGrid();

// Row/Col addressable "cells"
sg(1,1) = "Eastern Cities";
sg(2,1) = "Boston";
sg(3,1) = "New York";
sg(4,1) = "Atlanta";
// Skipping second 'column' is intentional and needs to be rendered correctly by ExportToExcel() [in other words, use Arrays, not List<string>]
sg(1,3) = "Western Cities";
sg(2,3) = "Los Angeles";
sg(3,3) = "Seattle";

Console.WriteLine(sg(2,1));  // Outputs "Boston"

sg.ExportToExcel(ws,row: 10);

是的，它只是一个二维字符串网格，使用 [string] 数组和一个额外的方法 [并且它从 1,1 开始，而不是 0,0]。

首先，我知道如何创建 getValue/setValue 方法。这是简单的出路。但是，我意识到我想让它使用起来“更简单”。我意识到我不知道如何声明/编写此代码以按照上面的“示例”使用。有可能吗？

Answer 1

您可以像这样为您的类创建索引器:

class StringGrid {
    // just a sample storage
    // might actually work if you only need to address whole rows
    // but not whole columns
    private readonly Dictionary<int, Dictionary<int, string>> _values = new Dictionary<int, Dictionary<int, string>>();
    // indexer 
    public string this[int x, int y]
    {
        get
        {
            // various checks omited
            return _values[x][y];
        }
        set
        {
            if (!_values.ContainsKey(x))
                _values.Add(x, new Dictionary<int, string>());
            _values[x][y] = value;
        }
    }
}

然后将所有的“(”改为“[”，“)”改为“]”即可:

sg[1, 1] = "Eastern Cities";
sg[2, 1] = "Boston";
sg[3, 1] = "New York";
sg[4, 1] = "Atlanta";
// Skipping second 'column' is intentional and needs to be rendered correctly by ExportToExcel() [in other words, use Arrays, not List<string>]
sg[1, 3] = "Western Cities";
sg[2, 3] = "Los Angeles";
sg[3, 3] = "Seattle";

Console.WriteLine(sg[2, 1]);  // Outputs "Boston"