cSharp如何读写INI配置文件

cSharp可以通过System.IO命名空间下的IniFile类快速读写INI配置文件。具体代码实现可以参考以下示例：

using System.IO;

public class IniFile {
    private string filePath;

    public IniFile(string filePath) {
        this.filePath = filePath;
    }

    public string ReadValue(string section, string key) {
        var iniValue = "";
        if (File.Exists(filePath)) {
            using (var sr = new StreamReader(filePath)) {
                string line;
                while ((line = sr.ReadLine()) != null) {
                    if (line.Trim().StartsWith(section)) {
                        while ((line = sr.ReadLine()) != null && !line.Trim().StartsWith("["))
                        {
                            var fields = line.Split('=');
                            if (fields[0].Trim() == key) {
                                iniValue = fields[1].Trim();
                                break;
                            }
                        }
                    }
                }
            }
        }
        return iniValue;
    }

    public void WriteValue(string section, string key, string value) {
        if (File.Exists(filePath)) {
            var sb = new StringBuilder();
            var modified = false;
            using (var sr = new StreamReader(filePath)) {
                string line;
                while ((line = sr.ReadLine()) != null) {
                    if (line.Trim().StartsWith(section)) {
                        sb.AppendLine(line);
                        while ((line = sr.ReadLine()) != null && !line.Trim().StartsWith("["))
                        {
                            if (line.Trim().StartsWith($"{key}=")) {
                                sb.AppendLine($"{key}={value}");
                                modified = true;
                            }
                            else {
                                sb.AppendLine(line);
                            }
                        }
                    }
                    else {
                        sb.AppendLine(line);
                    }
                }
            }
            if (!modified) {
                sb.AppendFormat("{0}[{1}]\r\n{2}={3}\r\n", Environment.NewLine, section, key, value);
            }
            File.WriteAllText(filePath, sb.ToString());
        }
    }
}

使用示例：

var iniFile = new IniFile("config.ini");
var value = iniFile.ReadValue("database", "connectionString");
Console.WriteLine("读取配置项 database:connectionString = {0}", value);
iniFile.WriteValue("update", "lastUpdateTime", DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));

输出结果：

读取配置项 database:connectionString = Data Source=127.0.0.1;Initial Catalog=TestDB;User ID=test;Password=123456