c# - ASP.NET 和实体框架中的网页给出了我正在努力解决的错误
问题描述
编辑：通过删除和重新创建实体数据库连接解决了这个问题
我正在创建一个网站，该网站将从表单中获取数据并将其存储在数据库中。我正在使用 C#、ASP.NET 和实体框架。我计划在本地服务器上托管这个网站，网站/服务器可能会重新启动，我需要代码不覆盖任何数据。我在 ASP.NET 和实体框架中的网页给出了我正在努力解决的错误。在我保存 db.SaveChanges(); 是错误到达的地方。
我曾经将我的 ID 设置为唯一标识符，它会通过，除非它不会创建新行。所以我将我的主键更改为 ID，它是一个 int。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Data.Entity.Core;
using System.Data.Entity.SqlServer;
using System.Data.Entity.Migrations;
using System.Data.Entity.ModelConfiguration;
using System.Data.Entity.Spatial;
using System.Data.Entity.Utilities;
using System.Data.Entity.Validation;
namespace EngiData
{
public partial class WebForm2 : System.Web.UI.Page
{
EandIForm model = new EandIForm();
string idValue = "";
string productionValue = "";
string machineValue = "";
string nameValue = "";
string workOrderNumberValue = "";
string partNumberValue = "";
string prefixValue = "";
string programNumberValue = "";
string tFileValue = "";
string revisionValue = "";
string programmerValue = "";
string machineCollisionValue = "";
string probingValue = "";
string feedSpeedValue = "";
string spindleDirectionvalue = "";
string depthOfCutValue = "";
string toolClearancesValue = "";
string toolCallOutValue = "";
string machineWorkOffSetValue = "";
string programDoesntMeetPrintValue = "";
string coolantCommandValue = "";
string gmValue = "";
string partTransferValue = "";
string programImprovementValue = "";
string otherValue = "";
string details = "";
EandIEntities3 myDBEntities = new EandIEntities3();
SqlConnection con = new SqlConnection(@"Data Source=ste1sqlt01;Initial Catalog=EandI;Persist Security Info=True;User ID=*******;Password=*******");
//con.Open();
//SqlCommand cmd = con.CreateCommand();
//cmd.CommandType = System.Data.CommandType.Text;
//SqlConnection con = new SqlConnection(@"Data Source=ste1sqlt01;Initial Catalog=EandI;Persist Security Info=True;User ID=********;Password=*************");
protected void Page_Load(object sender, EventArgs e)
{
}
protected void CheckBoxList1_SelectedIndexChanged(object sender, EventArgs e)
{
}
protected void submitButton_Click(object sender, EventArgs e)
{
if (productLineDropDown.SelectedItem.Value == "0")
{
ClientScript.RegisterStartupScript(this.GetType(), "myalert", "alert('" + "Please select a product line" + "' );", true);
}
else
if (productLineDropDown.SelectedItem.Value == "Long Sweep")
{
productionValue = "Long Sweep";
}
else
if (productLineDropDown.SelectedItem.Value == "Fittings")
{
productionValue = "Fittings";
}
else
if (productLineDropDown.SelectedItem.Value == "Plug Valve")
{
productionValue = "Plug Valve";
}
else
if (productLineDropDown.SelectedItem.Value == "Pumps")
{
productionValue = "Pumps";
}
else
if (productLineDropDown.SelectedItem.Value == "Union Connector")
{
productionValue = "Union Connector";
}
else
if (productLineDropDown.SelectedItem.Value == "Wellhead")
{
productionValue = "Wellhead";
}
else
if (productLineDropDown.SelectedItem.Value == "Well Service Pumps")
{
productionValue = "Well Service Pumps";
}
if (machineListDropDown.SelectedItem.Value == "0")
{
ClientScript.RegisterStartupScript(this.GetType(), "myalert", "alert('" + "Please select a machine." + "' );", true);
}
else
{
model.Machine = machineListDropDown.SelectedItem.Value;
}
if (nameTextbox0.Text != "")
{
nameValue = nameTextbox0.Text;
model.Submitter = nameValue.Trim();
}
if (workOrderTextbox0.Text != "")
{
workOrderNumberValue = workOrderTextbox0.Text;
model.Work_Order_Number = workOrderNumberValue.Trim();
}
model.Production_Line = productionValue.Trim();
//model.ID = Guid.NewGuid();
model.Part_Number = partNumberValue.Trim();
model.Program_Prefix = prefixValue.Trim();
model.Program_Number = programNumberValue.Trim();
model.TFile = tFileValue.Trim();
model.Revision = revisionValue.Trim();
model.Programmer = programmerValue.Trim();
model.Machine_Collision = machineCollisionValue.Trim();
model.Probing = probingValue.Trim();
model.Feed_Speed = feedSpeedValue.Trim();
model.Spindle_Direction = spindleDirectionvalue.Trim();
model.Depth_of_Cut = depthOfCutValue.Trim();
model.Tool_Clearance = toolClearancesValue.Trim();
model.Tool_Call_Outs = toolCallOutValue.Trim();
model.Machine_WorkOffSet = machineWorkOffSetValue.Trim();
model.Program_Doesnt_Match = programDoesntMeetPrintValue.Trim();
model.Coolant_Commands = coolantCommandValue.Trim();
model.GM_Code = gmValue.Trim();
model.Part_Transfer = partTransferValue.Trim();
model.Program_Improvement = programImprovementValue.Trim();
model.Other = otherValue.Trim();
model.Details = details.Trim();
using (EandIEntities3 db = new EandIEntities3())
{
db.EandIForms.Add(model);
db.SaveChanges();
}
productionValue = "";
machineValue = "";
nameValue = "";
workOrderNumberValue = "";
partNumberValue = "";
prefixValue = "";
programNumberValue = "";
tFileValue = "";
revisionValue = "";
programmerValue = "";
machineCollisionValue = "";
probingValue = "";
feedSpeedValue = "";
spindleDirectionvalue = "";
depthOfCutValue = "";
toolClearancesValue = "";
toolCallOutValue = "";
machineWorkOffSetValue = "";
programDoesntMeetPrintValue = "";
coolantCommandValue = "";
gmValue = "";
partTransferValue = "";
programImprovementValue = "";
otherValue = "";
details = "";
Response.Redirect("Submitted.aspx");
}
protected void clearButton_Click(object sender, EventArgs e)
{
}
}
}
这是我收到的错误
db.SaveChanges();
System.Data.Entity.Infrastructure.DbUpdateException was unhandled by user code
HResult=-2146233087
Message=An error occurred while updating the entries. See the inner exception for details.
Source=EntityFramework
StackTrace:
at System.Data.Entity.Internal.InternalContext.SaveChanges()
at System.Data.Entity.Internal.LazyInternalContext.SaveChanges()
at System.Data.Entity.DbContext.SaveChanges()
at EngiData.WebForm2.submitButton_Click(Object sender, EventArgs e) in C:\Users\hatchb.TP\Documents\Visual Studio 2015\Projects\EngiData\EngiData\WebForm2.aspx.cs:line 191
at System.Web.UI.WebControls.Button.OnClick(EventArgs e)
at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument)
at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)
at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)
at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
InnerException:
HResult=-2146233087
Message=An error occurred while updating the entries. See the inner exception for details.
Source=EntityFramework
StackTrace:
at System.Data.Entity.Core.Mapping.Update.Internal.UpdateTranslator.Update()
at System.Data.Entity.Core.EntityClient.Internal.EntityAdapter.<Update>b__2(UpdateTranslator ut)
at System.Data.Entity.Core.EntityClient.Internal.EntityAdapter.Update[T](T noChangesResult, Func`2 updateFunction)
at System.Data.Entity.Core.EntityClient.Internal.EntityAdapter.Update()
at System.Data.Entity.Core.Objects.ObjectContext.<SaveChangesToStore>b__35()
at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess)
at System.Data.Entity.Core.Objects.ObjectContext.SaveChangesToStore(SaveOptions options, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction)
at System.Data.Entity.Core.Objects.ObjectContext.<>c__DisplayClass2a.<SaveChangesInternal>b__27()
at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
at System.Data.Entity.Core.Objects.ObjectContext.SaveChangesInternal(SaveOptions options, Boolean executeInExistingTransaction)
at System.Data.Entity.Core.Objects.ObjectContext.SaveChanges(SaveOptions options)
at System.Data.Entity.Internal.InternalContext.SaveChanges()
InnerException:
Class=16
ErrorCode=-2146232060
HResult=-2146232060
LineNumber=1
Message=Operand type clash: uniqueidentifier is incompatible with int
Number=206
Procedure=""
Server=ste1sqlt01
Source=.Net SqlClient Data Provider
State=2
StackTrace:
at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)
at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)
at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)
at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString, Boolean isInternal, Boolean forDescribeParameterEncryption, Boolean shouldCacheForAlwaysEncrypted)
at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, Boolean inRetry, SqlDataReader ds, Boolean describeParameterEncryptionRequest)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry)
at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry)
at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
at System.Data.Entity.Infrastructure.Interception.DbCommandDispatcher.<NonQuery>b__0(DbCommand t, DbCommandInterceptionContext`1 c)
at System.Data.Entity.Infrastructure.Interception.InternalDispatcher`1.Dispatch[TTarget,TInterceptionContext,TResult](TTarget target, Func`3 operation, TInterceptionContext interceptionContext, Action`3 executing, Action`3 executed)
at System.Data.Entity.Infrastructure.Interception.DbCommandDispatcher.NonQuery(DbCommand command, DbCommandInterceptionContext interceptionContext)
at System.Data.Entity.Internal.InterceptableDbCommand.ExecuteNonQuery()
at System.Data.Entity.Core.Mapping.Update.Internal.DynamicUpdateCommand.Execute(Dictionary`2 identifierValues, List`1 generatedValues)
at System.Data.Entity.Core.Mapping.Update.Internal.UpdateTranslator.Update()
InnerException:
在我的数据库中，我的所有字段都是 varchar(50) 除了 ID 是具有标识规范的 INT。
我有一些代码被注释掉了，因为我试图通过几种不同的方法来做到这一点。有人能看到我的代码中的问题在哪里吗？
我的数据库名称是 EandIForm
我与实体框架的连接称为 EandIEntities3
解决方案
因此，要回答有关 uniqueidentifier 字段的问题，您需要向要进入数据库的模型添加一个新的 guid。你可以用这样的东西来做到这一点，在你的using陈述之前添加：
model.ID = Guid.NewGuid();
确保在文件顶部也有导入“系统”库的语句，因为 Guid 对象是其中的一部分。
using System;
.NET 代码中的 Guid 只是一个 16 位的唯一标识符，因此它会与数据库中的 ID 字段完美结合。
关于数据库如何工作的一些明确性 - count() 函数不会在服务器重新启动时更改，唯一会更改的时间是数据本身是否被清除或更改。希望这不会是一个问题，但如果你不确定我会问你公司的某个人，他们可能知道数据清理是如何工作的/如果它曾经发生过，然后从那里开始。
在添加新的 ID 时，您不需要检查 ID 是否为空或空，如您列出的 - Guid 的重点是它将 100% 的时间是唯一的，因此通过添加该 model.ID正如我在上面显示的那样，您应该能够避免检查该字段。
干杯!
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