Question

急。请教ASP C#中GridView出现的问题，谢谢各位大大，高分～求答案～谢谢～

我输入学号，出现学生数据，然后点击编辑，就可以更新此条学生数据，出错的那段代码如下：
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
sqlcon = new SqlConnection(strCon);
string sqlstr = "update 学生信息 set 学号='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[1].Controls[0])).Text.ToString().Trim() + "',姓名'"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[2].Controls[0])).Text.ToString().Trim() + "',性别='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[3].Controls[0])).Text.ToString().Trim() + "'出生日期='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[4].Controls[0])).Text.ToString().Trim() + "',年级='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[5].Controls[0])).Text.ToString().Trim() + "',专业='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[6].Controls[0])).Text.ToString().Trim() + "',电话='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[7].Controls[0])).Text.ToString().Trim() + "',Email='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[8].Controls[0])).Text.ToString().Trim() + "',QQ='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[9].Controls[0])).Text.ToString().Trim() + "', where id='"
+ GridView1.DataKeys[e.RowIndex].Value.ToString() + "'";
sqlcom = new SqlCommand(sqlstr, sqlcon);
sqlcon.Open();
sqlcom.ExecuteNonQuery();
sqlcon.Close();
GridView1.EditIndex = -1;
bind();
}

当修改完毕，点击更新后，VS就把下列代码用黄色的框框起来

string sqlstr = "update 学生信息 set 学号='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[1].Controls[0])).Text.ToString().Trim() + "',姓名'"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[2].Controls[0])).Text.ToString().Trim() + "',性别='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[3].Controls[0])).Text.ToString().Trim() + "'出生日期='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[4].Controls[0])).Text.ToString().Trim() + "',年级='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[5].Controls[0])).Text.ToString().Trim() + "',专业='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[6].Controls[0])).Text.ToString().Trim() + "',电话='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[7].Controls[0])).Text.ToString().Trim() + "',Email='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[8].Controls[0])).Text.ToString().Trim() + "',QQ='"
+ ((TextBox)(GridView1.Rows[e.RowIndex].Cells[9].Controls[0])).Text.ToString().Trim() + "', where id='"
+ GridView1.DataKeys[e.RowIndex].Value.ToString() + "'";

错误列表里面写的是：

无法将类型为“System.Web.UI.WebControls.Button”的对象强制转换为类型“System.Web.UI.WebControls.TextBox”。

请问是什么原因啊？
说详细点好吗？我具体应该怎么修改？我0基础，所以。。。麻烦各位了

我把那段代码从Cells[2]依次修改到Cells[10],它又说

指定的参数已超出有效值的范围。
参数名: index

我到底应该怎么办啊

55555555555555555555555555

我问的不是问题的原因，而是怎么处理这个问题

Answer 1

下面是我写的一段代码，你对照着试试，因为我不知道你的是不是都是textbox的形式，正好这段代码里有自定义的列，你可以参考。
前台：
<asp:GridView ID="GridView1" runat="server"
AutoGenerateColumns="False" CellPadding="4"
Font-Size="8pt" OnRowCancelingEdit="GridView1_RowCancelingEdit" OnRowDataBound="GridView1_RowDataBound" OnRowDeleting="GridView1_RowDeleting" OnRowUpdating="GridView1_RowUpdating" OnRowEditing="GridView1_RowEditing" EmptyDataText="no note!" PageSize="5" BackColor="White" BorderColor="#3366CC" BorderStyle="None" BorderWidth="1px" Font-Names="Arial">
<FooterStyle BackColor="#99CCCC" ForeColor="#003399" />
<RowStyle BackColor="White" ForeColor="#003399" />
<SelectedRowStyle BackColor="#009999" Font-Bold="True" ForeColor="#CCFF99" />
<PagerStyle BackColor="#99CCCC" ForeColor="#003399" HorizontalAlign="Left" />
<HeaderStyle BackColor="MediumBlue" Font-Bold="True" ForeColor="#CCCCFF" Font-Size="Small" />
<Columns>
<asp:CommandField CancelText="cancel" DeleteText="delete" EditText="edit"
InsertText="insert" NewText="new" SelectText="select" ShowDeleteButton="True"
UpdateText="update" />
<asp:CommandField ButtonType="Button" CancelText="cancel" DeleteText="delete" EditText="edit"
InsertText="insert" NewText="new" SelectText="select" ShowEditButton="True" UpdateText="update" />
<asp:BoundField DataField="inquireId" HeaderText="inquire id" ReadOnly="True" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="fixedAssetId" HeaderText="fixed asset id" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:TemplateField HeaderText="type">
<EditItemTemplate>
<%-- %><asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("type") %>'></asp:TextBox>--%>
<asp:DropDownList ID="ddl1" runat="server" DataSource='<%# ddl1bind()%>' DataValueField="type" DataTextField="type"></asp:DropDownList>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label1" runat="server" Text='<%# Bind("type") %>'></asp:Label>
</ItemTemplate>
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:TemplateField>
<asp:TemplateField HeaderText="soft type">
<EditItemTemplate>
<%-- %><asp:TextBox ID="TextBox2" runat="server" Text='<%# Bind("softType") %>'></asp:TextBox>--%>
<asp:DropDownList ID="ddl2" runat="server" DataSource='<%# ddl2bind()%>' DataValueField="softType" DataTextField="softType"></asp:DropDownList>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label2" runat="server" Text='<%# Bind("softType") %>'></asp:Label>
</ItemTemplate>
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:TemplateField>
<asp:BoundField DataField="brandOrSoftname" HeaderText="brand or software name" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="productModelOrEdition" HeaderText="product model or edition" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="configuration" HeaderText="configuration" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="servicetag" HeaderText="servicetag" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="os" HeaderText="OEM" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="warranty" HeaderText="warranty" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="annualCost" HeaderText="annual cost" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="purchaseDate" HeaderText="purchase date" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="price" HeaderText="price" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="ownCompany" HeaderText="own company" ReadOnly="True" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="userNumber" HeaderText="user number" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
<asp:BoundField DataField="remark" HeaderText="remark" >
<HeaderStyle Wrap="False" />
<ItemStyle Wrap="False" />
</asp:BoundField>
</Columns>
<EmptyDataRowStyle ForeColor="Red" />
<EditRowStyle Font-Size="Small" Wrap="False" />
</asp:GridView>

后台：
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
int i;
//执行循环，保证每条数据都可以更新
for (i = -1; i < GridView1.Rows.Count; i++)
{
//首先判断是否是数据行
if (e.Row.RowType == DataControlRowType.DataRow)
{
//当鼠标停留时更改背景色
e.Row.Attributes.Add("onmouseover", "c=this.style.backgroundColor;this.style.backgroundColor='#ccffff'");
//当鼠标移开时还原背景色
e.Row.Attributes.Add("onmouseout", "this.style.backgroundColor=c");
}
}
if (e.Row.RowType == DataControlRowType.DataRow)
{
if (e.Row.RowState == DataControlRowState.Normal || e.Row.RowState == DataControlRowState.Alternate)
{
((LinkButton)e.Row.Cells[0].Controls[0]).Attributes.Add("onclick", "javascript:return confirm('Are you want to delete\"" + e.Row.Cells[2].Text + "\"?')");
}
}
}
protected void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
{
GridView1.EditIndex = -1;
GridViewBind();
}
protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
string sqlstr = "delete from tb_ITInfo where inquireId='" + GridView1.DataKeys[e.RowIndex].Value.ToString() + "'";
SqlConnection conn = new SqlConnection();
conn.ConnectionString = ConfigurationManager.ConnectionStrings["sql_XellaConnectionString"].ToString();
conn.Open();
SqlCommand cmd = new SqlCommand(sqlstr, conn);
cmd.ExecuteNonQuery();
conn.Close();
GridViewBind();
}
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
try
{
string inquireid = GridView1.DataKeys[e.RowIndex].Value.ToString();
string fixedassetid = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[3].Controls[0])).Text;
string type = ((DropDownList)GridView1.Rows[e.RowIndex].Cells[4].FindControl("ddl1")).SelectedItem.Text;
string softtype = "";
if (type == "软件")
{
softtype = ((DropDownList)GridView1.Rows[e.RowIndex].Cells[5].FindControl("ddl2")).SelectedItem.Text;
}
else
{
softtype = "";
}
string brandorsoftname = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[6].Controls[0])).Text;
string model = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[7].Controls[0])).Text;
string configuration = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[8].Controls[0])).Text;
string servicetag = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[9].Controls[0])).Text;
string os = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[10].Controls[0])).Text;
string warranty = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[11].Controls[0])).Text;
string annualcost = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[12].Controls[0])).Text;
string purchasedate = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[13].Controls[0])).Text;
string price = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[14].Controls[0])).Text;
string owncompany = (GridView1.Rows[e.RowIndex].Cells[15]).Text;
string usernumber = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[16].Controls[0])).Text;
string remark = ((TextBox)(GridView1.Rows[e.RowIndex].Cells[17].Controls[0])).Text;
DateTime date1 = Convert.ToDateTime(warranty);
DateTime date2 = Convert.ToDateTime(purchasedate);
int number = Convert.ToInt32(usernumber);
string sqlstr = "update tb_ITInfo set fixedAssetId='" + fixedassetid + "',type='" + type + "',softType='" + softtype + "',brandOrSoftname='" + brandorsoftname + "',productModelOrEdition='" + model + "',configuration='" + configuration + "',servicetag='" + servicetag + "',os='" + os + "',warranty='" + warranty + "',annualCost='" + annualcost + "',purchaseDate='" + purchasedate + "',price='" + price + "',ownCompany='" + owncompany + "',userNumber='" + number + "',remark='" + remark + "' where inquireId= '" + inquireid + "'";
if (brandorsoftname == "")
{
Response.Write("<script>alert('Brand or software name can't be empty!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[6].Controls[0]));
}
else if (model == "")
{
Response.Write("<script>alert('Product model or edition can't be empty!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[7].Controls[0]));
}
else if (warranty == "")
{
Response.Write("<script>alert('Warranty can't be empty!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[11].Controls[0]));
}
else if (warranty.Length < 8)
{
Response.Write("<script>alert('Please check the format of warranty!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[11].Controls[0]));
}
else if (purchasedate == "")
{
Response.Write("<script>alert('Purchase date can't be empty!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[13].Controls[0]));
}
else if (purchasedate.Length < 8)
{
Response.Write("<script>alert('Please check the format of purchase date!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[13].Controls[0]));
}
else if (price == "")
{
Response.Write("<script>alert('Price date can't be empty!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[14].Controls[0]));
}
else if (usernumber == "")
{
Response.Write("<script>alert('User number date can't be empty!')</script>");
this.Page.SetFocus((TextBox)(GridView1.Rows[e.RowIndex].Cells[16].Controls[0]));
}
else
{
SqlConnection conn = new SqlConnection();
conn.ConnectionString = ConfigurationManager.ConnectionStrings["sql_XellaConnectionString"].ToString();
conn.Open();
SqlCommand cmd = new SqlCommand(sqlstr, conn);
cmd.ExecuteNonQuery();
cmd.Dispose();
GridView1.EditIndex = -1;
conn.Close();
GridViewBind();
}
}
catch
{
Response.Write("<script>alert('Please check the format!')</script>");
}
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
GridViewBind();
string P_Str_inquireid = GridView1.DataKeys[e.NewEditIndex].Value.ToString();
SqlConnection myConn = new SqlConnection();
myConn.ConnectionString = ConfigurationManager.ConnectionStrings["sql_XellaConnectionString"].ToString();
SqlCommand myCmd = new SqlCommand("Proc_GetITInfo", myConn);
myCmd.CommandType = CommandType.StoredProcedure;
//添加参数
SqlParameter inquireId = new SqlParameter("@inquireid", SqlDbType.VarChar, 50);
inquireId.Value = P_Str_inquireid;
myCmd.Parameters.Add(inquireId);
//执行过程
myConn.Open();
SqlDataReader rd = myCmd.ExecuteReader();
if (rd.Read())
{
HiddenField1.Value = rd["type"].ToString();
HiddenField2.Value = rd["softType"].ToString();
}
rd.Close();
myCmd.Dispose();
myConn.Close();
((DropDownList)GridView1.Rows[e.NewEditIndex].Cells[4].FindControl("ddl1")).SelectedValue = HiddenField1.Value;
((DropDownList)GridView1.Rows[e.NewEditIndex].Cells[5].FindControl("ddl2")).SelectedValue = HiddenField2.Value;
}
public SqlDataReader ddl1bind()
{
string sqlstr = "select distinct type from tb_Type where typeId!=0";
SqlConnection sqlcon = new SqlConnection();
sqlcon.ConnectionString = ConfigurationManager.ConnectionStrings["sql_XellaConnectionString"].ToString();
SqlCommand sqlcom = new SqlCommand(sqlstr, sqlcon);
sqlcon.Open();
return sqlcom.ExecuteReader();
}
public SqlDataReader ddl2bind()
{
string sqlstr = "select distinct softType from tb_SoftType";
SqlConnection sqlcon = new SqlConnection();
sqlcon.ConnectionString = ConfigurationManager.ConnectionStrings["sql_XellaConnectionString"].ToString();
SqlCommand sqlcom = new SqlCommand(sqlstr, sqlcon);
sqlcon.Open();
return sqlcom.ExecuteReader();
}

Answer 2

你的更新语句 姓名字段少了个=号..

Cells[1]到Cells[9]分别代表第2列到第10列..这其中有一列中间是Button控件,你检查一下...
-------------------------
GridView1.Rows[e.RowIndex].Cells[1].Controls[0])
这一句的意思是GridView更新行的第2列的第1个控件。。
Cells是单元格的意思，参数从0开始,Cells[1]也就是第2个单元格即第2列..
你出现错误的原因可能是你的GridView里的Cells里有两个控件,比方说同时有TextBox和BUTTON,你可以用Controls[参数]来选择哪一个控件,参数从0开始,0就是1...

Answer 3

报类型不能转换的错误，应该是你的单元格里的控件有类型是button，button的当然不能在程序中用textbox的类型来强制转换啊。另外，有效范围超出，是因为如果你的gridview如果只有10列，第10个单元格不是CELL[10]而是cell[9]，记住，一般都是从0开始为第一个的。

Answer 4

就是说你的类型是button,你偏要把它转换成 textbox当然就不行，

就像是一个字符串是aaa
string str="aaa";

你将它转换成数字，当然会出错了。
int m=(int)(str);

这样写肯定会出错的。

Answer 5

你肯定哪个地方button=TextBox了，你发的那段代码根本就没有这样的错误。

还有你这样写不是很好，用FindControl("Control_id")as ControlClass).text这样更好一点.