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如何在C#中获取运行时表的列名?

[英]How to get column names of table at runtime in C#?

假设我在SQLServer中有一个名为MyTable的表

ID FirstName   LastName
1  Harry       Dan
2  Maria       Vicente
3  Joe         Martin

现在,如果我必须在表中插入任何数据,我将简单地像这样触发Insert Query

INSERT INTO MyTable (ID, FirstName, LastName) VALUES (4, Smith, Dan);

但是,如果我事先不知道列名,我只知道表名。 那么有没有办法在运行时获取表的列名?

你可以使用sql-

SELECT name FROM sys.columns WHERE object_id = OBJECT_ID('TABLE_NAME') 

或者您可以查询SELECT TOP 0 * FROM TableName 然后,您可以获取列:

using(var reader = command.ExecuteReader())
{
    reader.Read();
    var table = reader.GetSchemaTable();
    foreach (DataColumn column in table.Columns)
    {
        Console.WriteLine(column.ColumnName);
    }
 }

使用纯C#/ .NET代码的另一个选项:首先是一个帮助器方法,这里返回一个简单的列名列表。 使用DataTable保存表架构信息意味着还可以为每列(fx)检索其他信息。 如果是AutoIncreament专栏等

    private IEnumerable<string> GetColumnNames(string conStr, string tableName)
    {
        var result = new List<string>();
        using (var sqlCon = new SqlConnection(conStr))
        {
            sqlCon.Open();
            var sqlCmd = sqlCon.CreateCommand();
            sqlCmd.CommandText = "select * from " + tableName + " where 1=0";  // No data wanted, only schema
            sqlCmd.CommandType = CommandType.Text;

            var sqlDR = sqlCmd.ExecuteReader();
            var dataTable = sqlDR.GetSchemaTable();

            foreach (DataRow row in dataTable.Rows) result.Add(row.Field<string>("ColumnName"));
        }

        return result;
    }

该方法可以称为:

        var sortedNames = GetColumnNames("Data Source=localhost;Initial Catalog=OF2E;Integrated Security=SSPI", "Articles").OrderBy(x => x);
        foreach (var columnName in sortedNames) Console.WriteLine(columnName);

只需通过此查询:

SELECT * FROM sys.columns
WHERE object_id = OBJECT_ID('dbo.[table_name]')

或者此查询:

SELECT COLUMN_NAME
FROM information_schema.columns
WHERE TABLE_NAME = [table_name]
ORDER BY COLUMN_NAME
var ColName = "";
        var model = new AttributeMappingSource().GetModel(typeof(DataClassesDataContext));
        foreach (var mt in model.GetTables())
        {
            if (mt.TableName == "dbo.Table_Name")
            {
                foreach (var dm in mt.RowType.DataMembers)
                {
                    ColName = dm.MappedName + ", ";
                    Response.Write(ColName);
                }
            }
        }

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