我有这个C#代码:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.OleDb;
using System.Data;
public partial class UpdateArticle : System.Web.UI.Page
{
public string ArticleTitle, ArticleBody, PostDate;
protected void Page_Load(object sender, EventArgs e)
{
string ArticleId;
try
{ ArticleId = Request.QueryString["ArticleId"].ToString();
string dpath = Server.MapPath(@"App_Data") + "/MySite.mdb";
string connectionstring = @"Data source='" + dpath + "';Provider='Microsoft.Jet.OLEDB.4.0';";
string q = string.Format("select * from tblArticles where ArticleId={0}", ArticleId);
OleDbConnection con = new OleDbConnection(connectionstring);
OleDbCommand cmd = new OleDbCommand(q, con);
con.Open();
cmd.ExecuteNonQuery();
OleDbDataAdapter da = new OleDbDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds, "tbl");
con.Close();
ArticleTitle = ds.Tables[0].Rows[0]["ArticleTitle"].ToString();
ArticleBody = ds.Tables[0].Rows[0]["ArticleBody"].ToString();
PostDate = ds.Tables[0].Rows[0]["PostDate"].ToString();
}
catch
{ }
string NewArticleTitle, NewArticleDate, NewArticleBody, ArticleId1;
try
{
NewArticleTitle = Request.Form["ArticleTitle"].ToString();
NewArticleDate = Request.Form["ArticleDate"].ToString();
NewArticleBody = Request.Form["ArticleBody"].ToString();
ArticleId1 = Request.QueryString["ArticleId"].ToString();
string dpath = Server.MapPath(@"App_Data") + "/MySite.mdb";
string connectionstring = @"Data source='" + dpath + "';Provider='Microsoft.Jet.OLEDB.4.0';";
OleDbConnection con = new OleDbConnection(connectionstring);
string QuaryString = string.Format("insert into tblArticles(ArticleTitle, ArticleBody, PostDate) values ('{0}','{1}','{2}') where ArticleId='{3}'", NewArticleTitle, NewArticleBody, NewArticleDate, ArticleId1);
OleDbCommand cmd = new OleDbCommand(QuaryString, con);
OleDbDataAdapter da = new OleDbDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds, "tbl");
con.Close();
}
catch { }
// Response.Redirect("ArticlesTable.aspx");
}}
我的代码中的问题是,当谈到这一行时:
ArticleId1 = Request.QueryString["ArticleId"].ToString();
它从try块退出。上面几行我写了这段代码:
ArticleId = Request.QueryString["ArticleId"].ToString();
它运作得很好。那么为什么下线不起作用呢? 当我第一次调试时:1:http://i.stack.imgur.com/CfKXL.png 在ASPX页面中提交表单后: 这是aspx代码:
<b>
כותרת המאמר :<br /></b><input id="Text1" type="text" name="ArticleTitle" value="<%=ArticleTitle %>"/><p></p>
<b>
תאריך פרסום: <br /></b><input id="Text2" type="text" name="ArticleDate" value="<%=PostDate %>"/><p></p>
<b>
תוכן המאמר: <br /></b> <textarea rows="10" cols="60" name="ArticleBody"><%=ArticleBody %></textarea>
<br />
<input id="Reset1" type="reset" value="נקה" />
<input id="Submit1" type="submit" value="שלח כתבה!" />
</form>
<p></p><p></p>
<a href="Default.aspx">חזור לדף הבית</a>
提交后(var没有得到Id值!)
答案 0 :(得分:0)
如果您的代码突然意外退出try
块,则会出现异常。
如果你的catch语句以catch { }
的形式抛弃该异常,那么你将永远不会看到它。
你应该完全删除try/catch
并让错误自然地冒出来,或者你应该抓住它并用它做点什么:
catch (Exception ex)
{
// However you want to handle things going wrong.
}
答案 1 :(得分:0)
您的代码抛出异常,很可能是因为Request.QueryString["ArticleId"]
超出了范围。我不确定为什么会这样,但这是最可能的解释。将catch {}
更改为catch (Exception e) {}
并在那里设置断点,以便检查异常。假设这是正在发生的事情,请在第一次尝试之外声明ArticleId1
,然后在设置ArticleId
后(在第一次尝试中)将其设置为行。