diff --git a/Providers/FreeSql.Provider.MySql/MySqlProvider.cs b/Providers/FreeSql.Provider.MySql/MySqlProvider.cs
index 2e032f27..461274fc 100644
--- a/Providers/FreeSql.Provider.MySql/MySqlProvider.cs
+++ b/Providers/FreeSql.Provider.MySql/MySqlProvider.cs
@@ -71,7 +71,7 @@ namespace FreeSql.MySql {
 		bool _isdisposed = false;
 		public void Dispose() {
 			if (_isdisposed) return;
-			(this.Ado as AdoProvider).Dispose();
+			(this.Ado as AdoProvider)?.Dispose();
 		}
 	}
 }
diff --git a/Providers/FreeSql.Provider.Oracle/OracleProvider.cs b/Providers/FreeSql.Provider.Oracle/OracleProvider.cs
index 2f2e7f44..16ae24c3 100644
--- a/Providers/FreeSql.Provider.Oracle/OracleProvider.cs
+++ b/Providers/FreeSql.Provider.Oracle/OracleProvider.cs
@@ -48,7 +48,7 @@ namespace FreeSql.Oracle {
 		bool _isdisposed = false;
 		public void Dispose() {
 			if (_isdisposed) return;
-			(this.Ado as AdoProvider).Dispose();
+			(this.Ado as AdoProvider)?.Dispose();
 		}
 	}
 }
diff --git a/Providers/FreeSql.Provider.PostgreSQL/PostgreSQLProvider.cs b/Providers/FreeSql.Provider.PostgreSQL/PostgreSQLProvider.cs
index bca60aa3..7f73ee10 100644
--- a/Providers/FreeSql.Provider.PostgreSQL/PostgreSQLProvider.cs
+++ b/Providers/FreeSql.Provider.PostgreSQL/PostgreSQLProvider.cs
@@ -98,7 +98,7 @@ namespace FreeSql.PostgreSQL {
 		bool _isdisposed = false;
 		public void Dispose() {
 			if (_isdisposed) return;
-			(this.Ado as AdoProvider).Dispose();
+			(this.Ado as AdoProvider)?.Dispose();
 		}
 	}
 }
diff --git a/Providers/FreeSql.Provider.SqlServer/SqlServerProvider.cs b/Providers/FreeSql.Provider.SqlServer/SqlServerProvider.cs
index a2d03c74..f6abcc0d 100644
--- a/Providers/FreeSql.Provider.SqlServer/SqlServerProvider.cs
+++ b/Providers/FreeSql.Provider.SqlServer/SqlServerProvider.cs
@@ -55,7 +55,7 @@ namespace FreeSql.SqlServer {
 		bool _isdisposed = false;
 		public void Dispose() {
 			if (_isdisposed) return;
-			(this.Ado as AdoProvider).Dispose();
+			(this.Ado as AdoProvider)?.Dispose();
 		}
 	}
 }
diff --git a/Providers/FreeSql.Provider.Sqlite/SqliteProvider.cs b/Providers/FreeSql.Provider.Sqlite/SqliteProvider.cs
index cfb02e77..73948db3 100644
--- a/Providers/FreeSql.Provider.Sqlite/SqliteProvider.cs
+++ b/Providers/FreeSql.Provider.Sqlite/SqliteProvider.cs
@@ -47,7 +47,7 @@ namespace FreeSql.Sqlite {
 		bool _isdisposed = false;
 		public void Dispose() {
 			if (_isdisposed) return;
-			(this.Ado as AdoProvider).Dispose();
+			(this.Ado as AdoProvider)?.Dispose();
 		}
 	}
 }