c# - Visual Studio Windows 窗体应用程序中出现未处理的异常。会是什么呢？

问题描述

我是一名学习计算机的大学生。对于我的编程任务，我需要在 Visual Studio 中制作一个 C# Windows 窗体应用程序，以允许用户在 Car Garage 的数据库中输入和存储信息。

我已经为客户详细信息创建了一个表和存储过程，但是当我测试和运行系统时，我在代码的执行非查询部分收到一条 Exception Unhandled 错误消息。输入所有数据后，当我按下表单上的提交按钮时，就会发生这种情况。

有谁知道为什么会这样，有人能把我推向正确的方向吗？

谢谢

（客户详细信息的存储过程）

Create Procedure [dbo].[AddDetails]
@CustomerName Varchar(50),
@CustomerAddress Varchar(50), 
@CustomerTelephone Varchar(50), 
@CustomerEmail Varchar(50), 
@CustomerType Varchar(15)

AS

Begin
Insert into [Customer]
([CustomerName]
,[CustomerAddress]
,[CustomerTelephone]
,[CustomerEmail]
,[CustomerType])
Values 
(@CustomerName
,@CustomerAddress
,@CustomerTelephone
,@CustomerEmail
,@CustomerType)
End

客户详细信息表

CREATE TABLE [dbo].[Customer] (
    [CustomerId]        INT          IDENTITY (1, 1) NOT NULL,
    [CustomerName]      VARCHAR (50) NOT NULL,
    [CustomerAddress]   VARCHAR (50) NOT NULL,
    [CustomerTelephone] VARCHAR (50) NOT NULL,
    [CustomerEmail]     VARCHAR (50) NOT NULL,
    [CustomerType]      VARCHAR (15) NOT NULL,
    CONSTRAINT [Pk_Name] PRIMARY KEY CLUSTERED ([CustomerId] ASC)
);
 ~ ~ ~
Code for the Add form 
 ~ ~ ~

private void btnSave_Click(object sender, EventArgs e)
        {
            if(txtName.Text =="" || txtAddress.Text =="" || txtPhoneNo.Text =="" || txtEmail.Text =="" || cboCustomerType.Text =="" 
                || txtMake.Text == "" || txtModel.Text =="" || txtRegistration.Text =="" || txtMaintenanceNo.Text =="" || cboService.Text ==""
                || txtDateofService.Text =="")
            {
                MessageBox.Show("Please enter all details");
            }
            else
            {
                using (SqlConnection sqlCon = new SqlConnection(connectionString))
                {
                    sqlCon.Open();
                    SqlCommand sqlcmd = new SqlCommand("AddDetails", sqlCon);
                    sqlcmd.CommandType = CommandType.StoredProcedure;

                    //add the data from the textbox into the @Name and store it in the database 
                    sqlcmd.Parameters.AddWithValue("@CustomerName", txtName.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@CustomerAddress", txtAddress.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@CustomerTelephone", txtPhoneNo.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@CustomerEmail", txtEmail.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@CustomerType", cboCustomerType.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@CarMake", txtMake.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@CarModel", txtModel.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@CarReg", txtRegistration.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@MaintenanceNo", txtMaintenanceNo.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@Service", cboService.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@Problems", txtProblems.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@ServiceHistory", txtServiceHistory.Text.Trim());
                    sqlcmd.Parameters.AddWithValue("@DateofService", txtDateofService.Text.Trim());





                    //execute query 
                    sqlcmd.ExecuteNonQuery();

                    //message box to show details have been entered 
                    MessageBox.Show("Details Saved");

标签： c#sql

c# - Visual Studio Windows 窗体应用程序中出现未处理的异常。会是什么呢？

问题描述

解决方案

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