DataTable

[Copy to clipboard] [ - ]CODE:
。。。。。
SqlDataReader reader1 = cmd1.ExecuteReader ();
DataTable dt = reader1 .GetSchemaTable
SetColumnHeaders(dt);

private void SetColumnHeaders(DataTable schema)//设置表头
{       
                       
    foreach (DataRow  row in schema.Rows )
    {
        listView1 .Columns .Add ( ??? ,95,HorizontalAlignment.Center );
    }
}

我想把DataTable中每一行的第一列(ColumnName)的内容添加为LISTVIEW的表头,请问怎么才能取到要的元素?
我看VB里面是在上面问号的地方用rom("ColumnName"),不知道C#里面应该怎么用?????
在下面的例子中实现了3个Join方法,其目的是把两个DataTable连接起来,相当于Sql的Inner Join方法,返回DataTable的所有列。
如果两个DataTable中的DataColumn有重复的话,把第二个设置为ColumnName+"_Second",下面是代码,希望对大家有所帮助。
using  System;
using  System.Data;

namespace  WindowsApplication1
{
    
public class SQLOps
    
{
        
public SQLOps()
        
{            
        }


        
public static DataTable Join (DataTable First, DataTable Second, DataColumn[] FJC, DataColumn[] SJC)

        
{

            
//创建一个新的DataTable

            DataTable table 
= new DataTable("Join");


            
// Use a DataSet to leverage DataRelation

            
using(DataSet ds = new DataSet())

            
{

                
//把DataTable Copy到DataSet中

                ds.Tables.AddRange(
new DataTable[]{First.Copy(),Second.Copy()});

                DataColumn[] parentcolumns 
= new DataColumn[FJC.Length];

                
for(int i = 0; i < parentcolumns.Length; i++)

                
{

                    parentcolumns[i] 
= ds.Tables[0].Columns[FJC[i].ColumnName];

                }


                DataColumn[] childcolumns 
= new DataColumn[SJC.Length];

                
for(int i = 0; i < childcolumns.Length; i++)

                
{

                    childcolumns[i] 
= ds.Tables[1].Columns[SJC[i].ColumnName];

                }



                
//创建关联

                DataRelation r 
= new DataRelation(string.Empty,parentcolumns,childcolumns,false);

                ds.Relations.Add(r);


                
//为关联表创建列

                
for(int i = 0; i < First.Columns.Count; i++)

                
{

                    table.Columns.Add(First.Columns[i].ColumnName, First.Columns[i].DataType);

                }


                
for(int i = 0; i < Second.Columns.Count; i++)

                
{

                    
//看看有没有重复的列,如果有在第二个DataTable的Column的列明后加_Second

                    
if(!table.Columns.Contains(Second.Columns[i].ColumnName))

                        table.Columns.Add(Second.Columns[i].ColumnName, Second.Columns[i].DataType);

                    
else

                        table.Columns.Add(Second.Columns[i].ColumnName 
+ "_Second", Second.Columns[i].DataType);

                }

               

                table.BeginLoadData();

                
foreach(DataRow firstrow in ds.Tables[0].Rows)

                
{

                    
//得到行的数据

                    DataRow[] childrows 
= firstrow.GetChildRows(r);

                    
if(childrows != null && childrows.Length > 0)

                    
{

                        
object[] parentarray = firstrow.ItemArray; 

                        
foreach(DataRow secondrow in childrows)

                        
{

                            
object[] secondarray = secondrow.ItemArray;

                            
object[] joinarray = new object[parentarray.Length+secondarray.Length];

                            Array.Copy(parentarray,
0,joinarray,0,parentarray.Length);

                            Array.Copy(secondarray,
0,joinarray,parentarray.Length,secondarray.Length);

                            table.LoadDataRow(joinarray,
true);

                        }


                    }


                }


                table.EndLoadData();

            }



            
return table;

        }



        
public static DataTable Join (DataTable First, DataTable Second, DataColumn FJC, DataColumn SJC)

        
{

            
return Join(First, Second, new DataColumn[]{FJC}new DataColumn[]{SJC});

        }


        
public static DataTable Join (DataTable First, DataTable Second, string FJC, string SJC)

        
{

            
return Join(First, Second, new DataColumn[]{First.Columns[FJC]}new DataColumn[]{First.Columns[SJC]});

        }



    }

}

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