怎么才能选中datagridview 中的checkbox????

Question

有个datagridview第一列是checkbox，但是没有能得到绑定数据,想在绑定数据后，再一行行判断是否应该选中，但是怎么选中？？下面这方法试了，不行？？求教高人？？？？？？？
string sql = "SELECT * FROM 课程";
            SqlMethod.bindDataGridView(dataGridView1 ,sql,"课程",ConnectionCom .getConnection());
            int sum = dataGridView1.Rows.Count;
            StringCom.showInformation(sum.ToString());
            for (int i = 0; i < sum;i++ )
            {
               //string courceid= dataGridView1.Rows[i].Cells[1].Value.ToString();
               ////StringCom.showInformation(courceid);
               ////StringCom.showInformation(temp.ToString());
               //if (ConnectionCom.IsHaveSelectCource(stuNumber, Convert .ToInt32(courceid)))
               //{                   DataGridViewCheckBoxCell checkcell = (DataGridViewCheckBoxCell)dataGridView1.Rows[i].Cells[0];
                   checkcell.Value = true;
               //}

Answer 1

<%@ Control Language="C#" AutoEventWireup="True" Inherits="include_SelectJs" Codebehind="SelectJs.ascx.cs" %>
<span  class="STYLE8" >选择：</span> 
<span id="select1" class="STYLE8" onclick="SettingChecked('selectAll');BackColor();this.style['color']='#33AA3F'">全部</span> -  
<span  id="select2"  class="STYLE8" onclick="SettingChecked();BackColor();this.style['color']='#33AA3F'">&nbsp;反选 &nbsp;</span>-  
<span  id="select3"  class="STYLE8" onclick="NoCheckSelect();BackColor();this.style['color']='#33AA3F'">&nbsp;不选</span>
<script type="text/javascript"  src="../JS/prototype.js"></script>
 <script language="javascript" type="text/javascript">
 
        //设置 CheckBox 的选择状态js反选 全选 多选框 兼容ie和firefox版本
        function SettingChecked(isCked)
        {
            var ck=document.getElementsByTagName("input");//意思是找到页面上所有 <input > 节点
             for(var i=0 ;i<ck.length;i++)
            {
                if(ck[i].type=="checkbox")
                    {
                    ck[i].checked=(isCked=="selectAll")? true :(!ck[i].checked);
                    }
            }
        }
        //判断选中提示。
        function DelAllItem(id,evt)
        {
           if(CkeckedTolNum(id)==0)
            {
                alert('<%=FSSoft.Web.UI.Language.Msg("00005") %>');
                return false;}
              else
               {return window.confirm('<%=FSSoft.Web.UI.Language.Msg("00008") %>');}
            }
        function CkeckedTolNum(cid)
        {
           var num =0;  
           var cks =document.getElementsByTagName("input");
            for(var i=0;i<cks.length;i++)
           { 
              //cks[i].id.indexOf(cid) = 0 时，说明 是以 cid 开头的 ID
              if(cks[i].type=="checkbox"  && cks[i].checked && cks[i].id.indexOf(cid)>=0)
              {num ++;}
            }
           return num;
         }
        function NoCheckSelect()//不选
        {
            var cks =document.getElementsByTagName("input");
            for(var i = 0; i < cks.length ; i++) 
            {
               if(cks[i].type.toLowerCase() =="checkbox"  && cks[i].checked)
               {
                //如果选择框选中则清空
                if(cks[i].checked.toString() == "true"){cks[i].checked = false;}
               }
            }
       }a
       function BackColor()//点击字体颜色变化
        {
        var q = 5;for(i=1 ; i<5;i++)
        {if($("select"+i)!=null){$("select"+i).style.color='';}}
        }
    </script>  <asp:CheckBox ID="single_Chk"  name="selectAll" runat="server" />
                              

Answer 2

你把单元格转换为DataGridViewCheckBoxCell?
你在DataGridViewCheckBoxCell checkcell = (DataGridViewCheckBoxCell)dataGridView1.Rows[i].Cells[0]; 
后面加一个
 MessageBox.Show(dataGridView1.Rows[i].Cells[i].ValueType.ToString());看看这个单元格的值是不是Boolean类型的，

Answer 3

 for (int i = 0; i < this.dataGridView1.Rows.Count; i++)
                {                   
                    if (this.dataGridView1.Rows[i].Cells[0].EditedFormattedValue.ToString().Trim() == "True")
                    {
                    }
                }

Answer 4

怎么才能在代码中设置checkbox的选中状态？？？？

Answer 5

好了，还是我这方法不错，开始不是有一个没有数据的么？？我生成个column放进去不就得了，后来如果选中了，看看数据中有没有，没有就插入，而没选中，也看看数据中有没有，有就删除！！！感谢大家支持！！！！！！！ 
namespace 学籍管理系统 
{ 
    public partial class SelectCource : Form 
    { 
        private string stuNumber; 
        public SelectCource(string stuNum) 
        { 
            InitializeComponent(); 
            stuNumber = stuNum; 
            GP.Text = stuNum+"的选课信息"; 
            bindDataGridView(); 
        } 
        protected void bindDataGridView() 
        { 
            string sql = "SELECT * FROM 课程"; 
            DataTable dt = SqlMethod.ReturnDataTable(ConnectionCom .getConnection (),sql,"课程"); 
            DataColumn dc = new DataColumn("select",System.Type.GetType("System.Boolean")); 
            dt.Columns.Add(dc); 
            dc.SetOrdinal(1); 
            int sum = dataGridView1.Rows.Count; 
            //StringCom.showInformation(sum.ToString()); 
            for (int i = 0; i < dt.Rows.Count;i++ ) 
            { 
              string courceid= dt.Rows[i]["课程编号"] .ToString(); 
              //StringCom.showInformation(courceid); 
              //StringCom.showInformation(temp.ToString()); 
              if (ConnectionCom.IsHaveSelectCource(stuNumber, Convert.ToInt32(courceid))) 
              { 
                  dt.Rows[i]["select"] = true; 
              } 
              else 
              { 
                  dt.Rows[i]["select"] = false; 
              } 
            } 
            dataGridView1.DataSource = dt; 
        }         private void SelectCource_Load(object sender, EventArgs e) 
        {         }         private void button1_Click(object sender, EventArgs e) 
        { 
            try 
            { 
                int sum = dataGridView1.Rows.Count; 
                for (int i = 0; i < sum; i++) 
                { 
                    //StringCom.showInformation(dataGridView1.Rows[i].Cells[0].Value.ToString()); 
                    int courseid = Convert.ToInt32(dataGridView1.Rows[i].Cells[0].Value.ToString()); 
                    //StringCom.showInformation(this.dataGridView1.Rows[i].Cells[1].EditedFormattedValue.ToString().Trim()); 
                    if (this.dataGridView1.Rows[i].Cells[1].EditedFormattedValue.ToString().Trim() == "True") 
                    { 
                        if (!ConnectionCom.IsHaveSelectCource(stuNumber, courseid)) 
                        { 
                            string sql = " insert into 选课(学号,课程编号) values(" + StringCom.QuoteStr(stuNumber) + "," + courseid + ")"; 
                            SqlMethod.InsertUpdateDeleteToDataBase(ConnectionCom.getConnection(), sql); 
                        } 
                    } 
                    else 
                    { 
                        if (ConnectionCom.IsHaveSelectCource(stuNumber, courseid)) 
                        { 
                            string sql = " delete from  选课 where 学号=" + StringCom.QuoteStr(stuNumber) + " and 课程编号=" + courseid; 
                            SqlMethod.InsertUpdateDeleteToDataBase(ConnectionCom.getConnection(), sql); 
                        } 
                    } 
                } 
                StringCom.showInformation("保存成功！"); 
                this.Dispose(); 
            } 
            catch (Exception err) 
            { 
                StringCom.showInformation(err.Message); 
            } 
        } 
    } 
}