make adapter获取多个语句 [英] make adapter gets multiple statement

问题描述

 SqlConnection con =  new  SqlConnection（ConfigurationManager.ConnectionStrings [  connection]。ConnectionString）; 
 SqlCommand com =  new  SqlCommand（）; 
 con.Open（）; 
 com.Connection = con; 
 
  //  获取此老师的课程ID  
  string  cmd1 =  从course_teacher中选择course_id，其中teacher_id =' + Session [  t_id] +   '; 
 SqlDataAdapter da1 =  new  SqlDataAdapter（cmd1，con）; 
 DataSet ds1 =  new  DataSet（）; 
 da1.Fill（ds1）; 
  string  cmd2 =  ; 
  for （ int  i =  0 ; i <  ds1.Tables [ 0 ]。Rows.Count; i ++）
 {
  int  courseid = Convert.ToInt32（ds1.Tables [ 0 ]。行[ i] [  course_id]。ToString（））; 
 cmd2 + =  从课程中选择（course_name +' - '+ class_name）course_id =' + courseid +  '; 
} 
 SqlDataAdapter da2 =  new  SqlDataAdapter（cmd2，con）; 
 DataSet ds2 =  new  DataSet（）; 
 da2.Fill（ds2）; 
 DropDownList1.DataSource = ds2; 
 DropDownList1.DataBind（）; 

问题是循环中的适配器只获取第一个语句...

解决方案

您好，



此代码：

 SqlDataAdapter da2 = new SqlDataAdapter（cmd2，con）; 
 DataSet ds2 = new DataSet（）; 
 da2.Fill（ds2）; 
 DropDownList1.DataSource = ds2; 
 DropDownList1.DataBind（）; 

在循环语句之外，这就是你无法得到的原因第二个适配器的结果。



干杯，

JAFC

以上所有你想拥有的数据数据集或数据表权利。所以请执行以下操作来解决您的问题

 //为此老师获取课程ID 
 string cmd1 =select course_id来自course_teacher，其中teacher_id =''+ Session [t_id] +''; 
 SqlDataAdapter da1 = new SqlDataAdapter（cmd1，con）; 
 DataSet ds1 = new DataSet（）; 
 da1.Fill（ds1）; 
 string cmd2 =; 
 Datatable dt-new DataTable（）; 
 for（int i = 0; i< ds1.Tables [0] .Rows.Count; i ++）
 {
 int courseid = Convert.ToInt32（ds1.Tables [0]。行[I] [ COURSE_ID]的ToString（））; 
 cmd2 =select（course_name +'' - ''+ class_name）来自course_id =''+ courseid +''的课程; 
 SqlDataAdapter da2 = new SqlDataAdapter（cmd2，con）; 
 DataSet ds2 = new DataSet（）; 
 da2.Fill（ds2）; 
 
 if（i = 0）
 {
 dt = ds2.tables [0]; 
} 
其他
 {
 dt.merge（ds2.tables [0]）; 
} 
} 
 
 DropDownList1.DataSource = dt; 
 DropDownList1.DataBind（）; 

我相信它会解决你的问题......

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["connection"].ConnectionString);
SqlCommand com = new SqlCommand();
con.Open();
com.Connection = con;

//get course id's for this teacher
string cmd1 = "select course_id from course_teacher where teacher_id='" + Session["t_id"] + "'";
SqlDataAdapter da1 = new SqlDataAdapter(cmd1, con);
DataSet ds1 = new DataSet();
da1.Fill(ds1);
string cmd2 = "";
for (int i = 0; i < ds1.Tables[0].Rows.Count; i++)
{
int courseid = Convert.ToInt32(ds1.Tables[0].Rows[i]["course_id"].ToString());
cmd2 += "select (course_name+'-'+class_name)from courses where course_id='" + courseid + "'";
}
SqlDataAdapter da2 = new SqlDataAdapter(cmd2, con);
DataSet ds2 = new DataSet();
da2.Fill(ds2);
DropDownList1.DataSource = ds2;
DropDownList1.DataBind();

the problem is the adapter in the loop gets just the first statement...

解决方案

Hi,

This code block:

SqlDataAdapter da2 = new SqlDataAdapter(cmd2, con);
DataSet ds2 = new DataSet();
da2.Fill(ds2);
DropDownList1.DataSource = ds2;
DropDownList1.DataBind();

is outside for loop statement and that is the reason why you can''t get results from the second adapter.

Cheers,
JAFC

all of the above you want to have the data in a dataset or datatable right. so pls do the following which should solve your problem

//get course ids for this teacher
string cmd1 = "select course_id from course_teacher where teacher_id=''" + Session["t_id"] + "''";
SqlDataAdapter da1 = new SqlDataAdapter(cmd1, con);
DataSet ds1 = new DataSet();
da1.Fill(ds1);
string cmd2 = "";
Datatable dt-new DataTable();
for (int i = 0; i < ds1.Tables[0].Rows.Count; i++)
{
int courseid = Convert.ToInt32(ds1.Tables[0].Rows[i]["course_id"].ToString());
cmd2 = "select (course_name+''-''+class_name)from courses where course_id=''" + courseid + "''";
SqlDataAdapter da2 = new SqlDataAdapter(cmd2, con);
DataSet ds2 = new DataSet();
da2.Fill(ds2);

if(i=0)
{
dt=ds2.tables[0];
}
else
{
dt.merge(ds2.tables[0]);
}
}

DropDownList1.DataSource = dt;
DropDownList1.DataBind();

and i am sure it will solve your problem.....

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