Question

我有一个方法如下所示。

public IResults GetResults(
            string code = "",
            string id = "",
            DateTime? registerDate = null,
            IEnumerable<Category> type = null,
            int pageNum = 1,
            bool all = false)
            {

                ....
                ........
            }

对于每个非null或非空参数，我希望将参数名称和值附加到URI字符串。

例如，如果参数code是非空的string，那么我希望将其作为result/?附加到标准URI results/?code=passedcodevalue。如果它是空的，那么就没有必要追加它。

同样，这些是构造URI的规则：

当code或id不为空时，请将其附加到 - results/? - 作为

results /？code = abc＆amp; id = xyz
registerDate未归零时，请将其附加到 - results/? - as 结果/码= ABC＆安培;？ID = XYZ＆安培; registerdate = 2004-06-29
type未归零时，请将其附加到 - results/? - as 结果/码= ABC＆安培;？ID = XYZ＆安培; registerdate = 2004-06-29＆安培;类型= QWERTY
当pagenum不是1时，请将其附加到 - results/? - as 结果/码= ABC＆安培;？ID = XYZ＆安培; registerdate = 2004-06-29＆安培;类型= QWERTY＆安培;页次= 5
当all不为false时将其附加到 - results/? - as 结果/码= ABC＆安培;？ID = XYZ＆安培; registerdate = 2004-06-29＆安培;类型= QWERTY＆安培;页次= 5＆安培;所有=真

执行此操作的最佳和通用方法是什么？

Answer 1

试试这个：

    public string GetResults(
        string code = "",
        string id = "",
        DateTime? registerDate = null,
        IEnumerable<Category> type = null,
        int pageNum = 1,
        bool all = false)
    {
        var result = "results/?";
        var firstFound = false;    //Used for add & to string
        for (int i = 0; i < 6; i++)
        {
            var partial = string.Empty;
            switch (i)
            {
                case 0:
                    partial = GetIfNotEmpty("code", code);
                    break;
                case 1:
                    partial = GetIfNotEmpty("id", id);
                    break;
                case 2:
                    partial = GetIfNotEmpty("registerDate", registerDate);
                    break;
                case 3:
                    partial = GetIfNotEmpty("type", type);
                    break;
                case 4:
                    partial = GetIfNotEmpty("pageNum", pageNum);
                    break;
                default:
                    partial = GetIfNotEmpty("all", all);
                    break;
            }
            if (string.IsNullOrWhiteSpace(partial))
                continue;
            if (firstFound)
                result += "&";
            else
                firstFound = true;
            result += partial;
        }
        return result;
    }

    private string GetIfNotEmpty<T>(string name, T value)
    {
        if (value == null)
            return string.Empty;
        if (value is IEnumerable)
        {
            var enumerableFinalString = string.Empty;
            foreach (var item in ((IEnumerable)value))
            {
                enumerableFinalString += item.ToString();
            }
            return string.Format("{0}={1}", name, enumerableFinalString);
        }
        return string.Format("{0}={1}", name, value.ToString());
    }

要附加到字符串的C＃非null参数

1 个答案: