Question

怎么判断数据库中是否含有某个表

Answer 1

/// <summary>
/// 执行一条计算查询结果语句，返回查询结果（object）。
/// </summary>
/// <param name="SQLString">计算查询结果语句</param>
/// <returns>查询结果（object）</returns>
public static object GetSingle(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
using (SqlCommand cmd = new SqlCommand(SQLString, connection))
{
try
{
connection.Open();
object obj = cmd.ExecuteScalar();
if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch (System.Data.SqlClient.SqlException e)
{
connection.Close();
throw e;
}
}
}
}

/// <summary>
/// 判断是否存在某表
/// </summary>
/// <param name="tableName">表名称</param>
/// <returns>是否存在</returns>
public static bool ColumnExists(string tableName)
{
string sql = "select count(1) from syscolumns where [id]=object_id('" + tableName + "') ";
object res = GetSingle(sql);
if (res == null)
{
return false;
}
return Convert.ToInt32(res) > 0;
}

connectionString 是数据库链接字符串
直接复制粘贴就可以用