How can I determine whether a column exists in a SQL Server CE table with C#?

Question

The legacy code does it this way:

public bool isValidField(string tableName, string fieldName)
{
    bool retVal;
    string tblQuery = string.Format(\"SELEC         


        

Answer 1

    public bool IsValidField(SqlCeConnection objCon, string tableName, string columnName)
    {
        const string query = "SELECT 1 FROM INFORMATION_SCHEMA.COLUMNS"
                                + " WHERE TABLE_NAME = @TABLENAME AND"
                                + " COLUMN_NAME = @COLUMNNAME";

        using (var cmd = new SqlCeCommand(query, objCon))
        {
            cmd.Parameters.Add("@TABLENAME", SqlDbType.NVarChar, 128).Value = tableName;
            cmd.Parameters.Add("@COLUMNNAME", SqlDbType.NVarChar, 128).Value = columnName;
            var objvalid = cmd.ExecuteScalar(); // will return 1 or null
            return objvalid != null;
        }
    }

Answer 2

You can just query the information schema tables to get the information you want:

public bool isValidField(string tableName, string columnName)
{
    var tblQuery = "SELECT 1 FROM INFORMATION_SCHEMA.COLUMNS"
                   + " WHERE TABLE_NAME = @tableName AND"
                   + " COLUMN_NAME = @columnName";

    SqlCeCommand cmd = objCon.CreateCommand();
    cmd.CommandText = tblQuery;
    var tblNameParam = new SqlCeParameter(
        "@tableName",
        SqlDbType.NVarChar,
        128);

    tblNameParam.Value = tableName
    cmd.Parameters.Add(tblNameParam);
    var colNameParam = new SqlCeParameter(
        "@columnName",
        SqlDbType.NVarChar,
        128);

    colNameParam.Value = columnName
    cmd.Parameters.Add(colNameParam);
    object objvalid = cmd.ExecuteScalar(); // will return 1 or null
    return objvalid != null;
}