JeffreySu/WeiXinMPSDK · error · ArgumentOutOfRangeException

certType

Error message

certType

What it means

TenPaySignerFactory.GetSigner only supports CertType.RSA (SHA256WithRSASigner) and CertType.SM (SM3WithSM2Signer); any other CertType value reaches the default arm and throws ArgumentOutOfRangeException(nameof(certType)).

Solutions

1. Set EncryptionType to CertType.RSA (standard) or CertType.SM (国密) in your TenpayV3Setting.
2. Validate any config-sourced CertType with Enum.IsDefined before use.
3. If you need an unsupported scheme, upgrade the Senparc.Weixin.TenPay package to a version that supports it.

Example fix

// before
var certType = (CertType)0; // undefined
// after
var certType = CertType.RSA; // or CertType.SM

if (!Enum.IsDefined(typeof(CertType), certType) || certType is not (CertType.RSA or CertType.SM))
    throw new InvalidOperationException("EncryptionType must be RSA or SM.");

bool IsSupportedCertType(CertType t) => t is CertType.RSA or CertType.SM;

try { var signer = TenPaySignerFactory.GetSigner(certType); }
catch (ArgumentOutOfRangeException) { logger.LogError("Unsupported certType {CertType}", certType); }

When it happens

Trigger: Constructing TenPayHttpClient (which calls TenPayCertFactory/GetSigner) with an EncryptionType/CertType that is not RSA or SM — typically an invalid enum cast or an unbound default 0 value if the enum doesn't define it.

Common situations: Config value parsed into an undefined enum member; int cast to CertType; new CertType member added by a newer WeChat Pay scheme but the installed Senparc library version doesn't support it.

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

• requestMethod
• ArgumentOutOfRangeException (certType: RSA/SM only)
• sendType
• 没有设置证书加密类型（EncryptionType）
• 超时时间必须大于 0，或使用 Timeout.Infinite。

AI-assisted analysis of JeffreySu/WeiXinMPSDK@be573f6f94 (2026-09-12). Data as JSON: /api/errors/0803374dfd29911f. Report an issue: GitHub.

Appendix: source

Thrown at src/Senparc.Weixin.TenPay/Senparc.Weixin.TenPayV3/TenPayHttpClient/TenPaySignerFactory.cs:29

    /// </summary>
    public static class TenPayCertFactory
    {
        /// <summary>
        /// 获取签名对象
        /// </summary>
        /// <param name="certType"></param>
        /// <returns></returns>
        /// <exception cref="ArgumentOutOfRangeException"></exception>
        public static ISigner GetSigner(CertType certType)
        {
            switch (certType)
            {
                case CertType.RSA:
                    return new SHA256WithRSASigner();
                case CertType.SM:
                    return new SM3WithSM2Signer();
                default:
                    throw new ArgumentOutOfRangeException(nameof(certType));
            }
        }

        /// <summary>
        /// 获取验签对象
        /// </summary>
        /// <param name="certType"></param>
        /// <returns></returns>
        /// <exception cref="ArgumentOutOfRangeException"></exception>
        public static IVerifier GetVerifier(CertType certType)
        {
            switch (certType)
            {
                case CertType.RSA:
                    return new SHA256WithRSAVerifier();
                case CertType.SM:
                    return new SM3WithSM2Verifier();
                default:

View on GitHub (pinned to be573f6f94)