GridView1中CheckBox多选时，点击外面的button按钮显示信息问题

[Dotar]

GridView中CheckBox多选时，点击外面的button按钮显示信息到GridView2中
选择代码：
public void bind()
{
DataTable ds = DB.GetDataTable("select * from 表");

this.GridView1.DataSource = ds;
this.GridView1.DataKeyNames = new string[] { "ID" };
this.GridView1.DataBind();


}
protected void Button1_Click(object sender, EventArgs e)
{
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
if (cbox.Checked == true)
{
DataTable ds = DB.GetDataTable("select 字段 from 表 where ID=" + Convert.ToUInt32(GridView1.DataKeys[i].Value) + "");

this.GridView2.DataSource = ds;
this.GridView2.DataBind();
}
}
bind();

}


如果我选择两行，能够显示到GridView2中两行信息。目前上面的代码只能显示选择的最后一行的信息，求大侠给思想，给方法
我试过while(cbox.Checked == true)不行，求高手指点！！！！！！！！！！！！！！！

[pgxuser]

很明显，执行for循环时，每次都把原来的绑定覆盖了。最后执行的绑定就是最终显示的了。
DataTable ds = DB.GetDataTable("select 字段 from 表 where ID=" + Convert.ToUInt32(GridView1.DataKeys[i].Value) + "");

this.GridView2.DataSource = ds;
this.GridView2.DataBind();

[Dotar]

[Quote=引用 1 楼 pgxuser 的回复:]
很明显，执行for循环时，每次都把原来的绑定覆盖了。最后执行的绑定就是最终显示的了。
DataTable ds = DB.GetDataTable("select 字段 from 表 where ID=" + Convert.ToUInt32(GridView1.DataKeys[i].Value) + "");

this.GridView2.DataSource = ds;
……
[/Quote]

怎么不覆盖呢？

[pgxuser]

我的思路是，将所有选中的Id用for循环集合起来，
最后 string sqlStr=("select 字段 from 表 where ID in "+ID集合）;
DataTable ds = DB.GetDataTable(sqlStr);
this.GridView2.DataSource = ds;
this.GridView2.DataBind();

[pgxuser]

string IDs="";//声明变量ID集合
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
if (cbox.Checked == true)
{
ID+= Convert.ToUInt32(GridView1.DataKeys[i].Value) + ",";
}
}
if(IDs.Length>0)
{
IDs=IDs.substring(0,IDs.Length-1);
}

[孟子E章]

你应该这样
protected void Button1_Click(object sender, EventArgs e)
{
DataTable ds
String where = "";
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
if (cbox.Checked == true)
{
where += " ID = " + GridView1.DataKeys[i].Value.ToString() + " Or"



}
}
if(where!="")
{
where = where.TrimEnd("Or");
ds = DB.GetDataTable("select 字段 from 表 where " + where);
this.GridView2.DataSource = ds;
this.GridView2.DataBind();
}

}

[孟子E章]

或者
protected void Button1_Click(object sender, EventArgs e)
{
DataTable ds
String where = "(";
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
if (cbox.Checked == true)
{
where += GridView1.DataKeys[i].Value.ToString() + ","
}
}
if(where!="(")
{
where = where.TrimEnd(",") + ")";
ds = DB.GetDataTable("select 字段 from 表 where ID IN " + where);
this.GridView2.DataSource = ds;
this.GridView2.DataBind();
}

}

[lijing5916]

[Quote=引用 4 楼 pgxuser 的回复:]
string IDs="";//声明变量ID集合
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
if (cbox.Checked == true)
{
ID+= Co……
[/Quote]

[zou0702tao]

string sql="select 字段 from 表 where "
for(...)
{
string str="or ID="+ Convert.ToUInt32(GridView1.DataKeys[i].Value);
sql+=str;
}
自己写代码去掉第一个or

[pgxuser]

[Quote=引用 3 楼 pgxuser 的回复:]
我的思路是，将所有选中的Id用for循环集合起来，
最后 string sqlStr=("select 字段 from 表 where ID in "+ID集合）;
DataTable ds = DB.GetDataTable(sqlStr);
this.GridView2.DataSource = ds;
this.GridView2.DataBind();
[/Quote]
[Quote=引用 4 楼 pgxuser 的回复:]
string IDs="";//声明变量ID集合
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
if (cbox.Checked == true)
{
ID+= Co……
[/Quote]
结合到一起就行了。

[暖枫无敌]

你这样循环，肯定取的是最后一条记录了，前面的都被后面一条覆盖掉了。

public void bind()
  {
  DataTable ds = DB.GetDataTable("select * from 表");

  this.GridView1.DataSource = ds;
  this.GridView1.DataKeyNames = new string[] { "ID" };
  this.GridView1.DataBind();
   
   
  }

protected void Button1_Click(object sender, EventArgs e)
{
   StringBuilder sb =new StringBuilder();
   for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
  {
        CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
        if (cbox.Checked == true)
       {
            sb.Append(GridView1.DataKeys[i].Value+",");
       }  
  }
  DataTable ds = DB.GetDataTable("select 字段 from 表 where ID in (" +sb.ToString().TrimEnd(',') +")");
  this.GridView2.DataSource = ds;
  this.GridView2.DataBind();
}

[h_zai888]

就是for循环覆盖了前面的绑定 只显示最后一条记录
[Quote=引用 5 楼 net_lover 的回复:]
你应该这样
protected void Button1_Click(object sender, EventArgs e)
{
DataTable ds
String where = "";
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)Grid……
[/Quote]

[Dotar]

[Quote=引用 10 楼 taomanman 的回复:]
你这样循环，肯定取的是最后一条记录了，前面的都被后面一条覆盖掉了。



C# code

public void bind()
{
DataTable ds = DB.GetDataTable("select * from 表");

this.GridView1.DataSource = ds;
this.GridView1.DataKeyNames = ……
[/Quote]

正解！感谢2楼给了我思想，我回来后已经有这么多人回答，感谢所有回答的人，自己解决的方法：
protected void Button1_Click(object sender, EventArgs e)
{
string sql = "select 字段 from 表 where ID in(";
for (int i = 0; i <= GridView1.Rows.Count - 1; i++)
{
CheckBox cbox = (CheckBox)GridView1.Rows[i].FindControl("CheckBox1");
if (cbox.Checked == true)
{
sql = sql + GridView1.DataKeys[i].Value + ",";

}
}
sql = sql.Substring(0, sql.Length - 1) + ")";
DataTable ds = DB.GetDataTable(sql);

this.GridView2.DataSource = ds;
this.GridView2.DataBind();
bind();
}