Attribute 'Table' is not valid on this declaration type. It is valid on 'type' declarations only.

Question

I'm doing the Output Binding in Azure Functions .NET 6.

Whatever the input data I'm receiving, that passing to the table in the table storage but two errors I'm getting.

1. Getting Table Attribute Error in declaration:

[FunctionName("IOBindingTimerTrigger")]
        [return: Table("DTOTable")]
        public static async Task<MyDTO> IOBindingTimerTrigger([TimerTrigger("0 */2 * * * *", RunOnStartup = true)] TimerInfo timerInfo,
            [Blob("devhack/input.txt", FileAccess.Read, Connection = "AzureWebJobsStorage")] Stream stream,
            ILogger log)
        {
            StreamReader streamReader = new StreamReader(stream);
            JObject jObject = JsonConvert.DeserializeObject<JObject>(streamReader.ReadToEnd());
            MyDTO dto = new MyDTO()
            {
                text = jObject
            };
            return dto;
        }
    }

        public class MyDTO : TableEntity
        {
            public MyDTO()
            {
                this.PartitionKey = Guid.NewGuid().ToString();
                this.RowKey = "12345";
            }

            public JObject text { get; set; }
        }
}

2. It is working in my colleague's system but text object not adding to table. Only Partition key and row key is adding. Jobject data is not adding to the text object.

Could anyone help me where I'm doing wrong?

Answer 1

Vaishnavi Thank you for posting this question in Microsoft Q&A.

For the first part, based on discussion: 'Attribute 'Table' is not valid for this declaration type’, you are missing extension either Microsoft.Azure.WebJobs.Extensions.Tables or Microsoft.Azure.WebJobs.Extensions.Storage depending on the version you use as described here. Adding the necessary extension should fix this issue.

In the Second part, you are trying to save JObject directly and I don't think Azure Table Storage supports it. You would have to process JSON data and save it in Table Storage and here is an example: https://learn.microsoft.com/en-us/azure/azure-functions/functions-bindings-example?tabs=csharp-class-library (similar thread: https://learn.microsoft.com/en-us/answers/questions/39797/parse-json-array-to-azure-table-storage). Or you can save it as string (JObject) and then process it in your application code.

I hope this helps with your question and let me know if any questions.

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