DropDownList控件绑定数据源的三种方法

本文给大家分享web  中 dropdownlist绑定数据源的几种方式，先给大家分享三种常见的方式，具体详情如下所示：

 第一种  

   this.ddltype.datatextfield = "btname";//显示的值
        this.ddltype.datavaluefield = "btid";//获取dropdownlist中的值
        ddltype.datasource = service.getbusinesstypeall("");
        this.ddltype.databind();

第二种           

 datatable dt_getbusinessname = service.getbusinesstypeall("");
        //表中无数据的话直接返回
        if (dt_getbusinessname == null)
          return;
        for (int i = 0; i < dt_getbusinessname.rows.count; i++)
        {
          ddltype.items.add(new listitem(dt_getbusinessname.rows[i]["btname"].tostring().trim(),//显示的值
          dt_getbusinessname.rows[i]["btid"].tostring().trim()));
        }s
        ddltype.items.add(new listitem("全部", "-1"));
        ddltype.text = "全部";

如何选中dropdownlist1中的值用

protected void dropdownlist1_selectedindexchanged(object sender, eventargs e)
  {
    this.textbox1.text = this.dropdownlist1.selecteditem.text.tostring();
  }

第三种：

 protected void ddl_bumen_selectedindexchanged(object sender, eventargs e)
  {
    if (this.ddl_bumen.text != "选择部门")
    {
      int id = int32.parse(this.ddl_bumen.text);
      sqlparameter bumen = new sqlparameter("@dept_id", id);
      ilist<lbemploy> list = bllgeneric.select<lbemploy>(commandtype.storedprocedure, "lb_liandong", bumen);
      //配置数据源
      this.ddl_em.datasource = list;
      //绑定字段属性
      this.ddl_em.datatextfield = "em_name";
      this.ddl_em.datavaluefield = "em_name";
      //绑定控件
      this.ddl_em.databind();
    }
    else
    {
      this.response.write(string.format(getredirect.winalert, "请选择部门"));
      this.ddl_bumen.focus();
      return;
    }
  }

下面看下dropdownlist控件动态绑定数据源的两种方法

dropdownlist控件绑定数据源示例，本文提供两种方法，皆为动态绑定

动态绑定方法一：动态绑定数据库中的字段。

sqlconnection conn = utilitysqlclass.operatedatabase.returnconn();
string strsql = "select * from companytype";
sqldataadapter ada = new sqldataadapter(strsql, conn);
dataset ds = new dataset();
ada.fill(ds, "companytype");
dropdownlist1.datasource = ds.tables["companytype"].defaultview;
dropdownlist1.datavaluefield = ds.tables["companytype"].columns[1].columnname;
dropdownlist1.datatextfield = ds.tables["companytype"].columns[1].columnname;
dropdownlist1.databind();
ds.dispose();

动态绑定方法二：利用dropdownlist.items.add方法。

protected void page_load(object sender, eventargs e)
{
if (!ispostback)
{
sqlconnection conn = utilitysqlclass.operatedatabase.returnconn();
try
{
conn.open();
this.dropdownlist1.items.add("");
string strsql = "select companytype from companytype";
sqlcommand com = new sqlcommand(strsql, conn);
sqldatareader dr = com.executereader();
while (dr.read())
{
this.dropdownlist1.items.add(dr["companytype"].tostring());
}
}
catch (exception ex)
{
response.write("<scirpt>alert('" + ex.message.tostring() + "')</script>");
}
finally
{
conn.close();
}
}
}

第一种方法：

 string connstring = configurationsettings.appsettings["connectionstring"];
     //创建一个sqlconnection
     sqlconnection conn = new sqlconnection( connstring );    
     string sql_select = "select id, itemname from ddlitem order by id desc";
     //构造一个sqldataadapter
     sqldataadapter myadapter = new sqldataadapter( sql_select, conn);
     //开始读取数据
     conn.open();
     dataset dataset = new dataset();
     myadapter.fill( dataset,"table1" );
     conn.close();
     //开始绑定dropdownlist
     //指定dropdownlist使用的数据源
     dropdownlist1.datasource = dataset.tables["table1"].defaultview;
     //指定dropdownlist使用的表里的那些字段
     dropdownlist1.datatextfield = "itemname"; //dropdownlist的text的字段
     dropdownlist1.datavaluefield = "id";//dropdownlist的value的字段
     dropdownlist1.databind();

第二种方法：

con.open();
    sqlcommand cmd = new sqlcommand(strsql,con);
    sqldatareader dr = cmd.executereader();
    while (dr.read())
    {   
      dropdownlist1.items.add(new listitem(dr["status"].tostring(), dr["status_id"].tostring()));
    }

以上所述是小编给大家介绍的dropdownlist控件绑定数据源的三种方法，希望对大家有所帮助