如何给DataTable修改里面的列和值

[since66]

有个DataTable里面的数据，如图:

列 A B C
行 1 2 3
行 1 2 3
行 1 2 3

我想写个方法
/// <summary>
/// 填充dt
/// </summary>
/// <param name="dt">dt名字</param>
/// <param name="Columns">列名</param>
/// <param name="value">列值</param>
/// <param name="i">第几列</param>
/// <returns></returns>
private DataTable getTB(DataTable dt, string Columns,string value,int i)
{
}

这个方法要求可以添加其他列，例如D,E,f....不定，可以添加行A[3]=5或修改B[0]=10等等,请问怎么写？谢谢！

[charles0525]

学习一下临时表就会了 ！

[liuyeede]

下面的代码出自msdn：

private System.Data.DataSet dataSet;

private void MakeDataTables()
{
    // Run all of the functions. 
    MakeParentTable();
    MakeChildTable();
    MakeDataRelation();
    BindToDataGrid();
}

private void MakeParentTable()
{
    // Create a new DataTable.
    System.Data.DataTable table = new DataTable("ParentTable");
    // Declare variables for DataColumn and DataRow objects.
    DataColumn column;
    DataRow row;

    // Create new DataColumn, set DataType, 
    // ColumnName and add to DataTable.    
    column = new DataColumn();
    column.DataType = System.Type.GetType("System.Int32");
    column.ColumnName = "id";
    column.ReadOnly = true;
    column.Unique = true;
    // Add the Column to the DataColumnCollection.
    table.Columns.Add(column);

    // Create second column.
    column = new DataColumn();
    column.DataType = System.Type.GetType("System.String");
    column.ColumnName = "ParentItem";
    column.AutoIncrement = false;
    column.Caption = "ParentItem";
    column.ReadOnly = false;
    column.Unique = false;
    // Add the column to the table.
    table.Columns.Add(column);

    // Make the ID column the primary key column.
    DataColumn[] PrimaryKeyColumns = new DataColumn[1];
    PrimaryKeyColumns[0] = table.Columns["id"];
    table.PrimaryKey = PrimaryKeyColumns;

    // Instantiate the DataSet variable.
    dataSet = new DataSet();
    // Add the new DataTable to the DataSet.
    dataSet.Tables.Add(table);

    // Create three new DataRow objects and add 
    // them to the DataTable
    for (int i = 0; i<= 2; i++)
    {
        row = table.NewRow();
        row["id"] = i;
        row["ParentItem"] = "ParentItem " + i;
        table.Rows.Add(row);
    }
}

private void MakeChildTable()
{
    // Create a new DataTable.
    DataTable table = new DataTable("childTable");
    DataColumn column;
    DataRow row;

    // Create first column and add to the DataTable.
    column = new DataColumn();
    column.DataType= System.Type.GetType("System.Int32");
    column.ColumnName = "ChildID";
    column.AutoIncrement = true;
    column.Caption = "ID";
    column.ReadOnly = true;
    column.Unique = true;

    // Add the column to the DataColumnCollection.
    table.Columns.Add(column);

    // Create second column.
    column = new DataColumn();
    column.DataType= System.Type.GetType("System.String");
    column.ColumnName = "ChildItem";
    column.AutoIncrement = false;
    column.Caption = "ChildItem";
    column.ReadOnly = false;
    column.Unique = false;
    table.Columns.Add(column);

    // Create third column.
    column = new DataColumn();
    column.DataType= System.Type.GetType("System.Int32");
    column.ColumnName = "ParentID";
    column.AutoIncrement = false;
    column.Caption = "ParentID";
    column.ReadOnly = false;
    column.Unique = false;
    table.Columns.Add(column);

    dataSet.Tables.Add(table);

    // Create three sets of DataRow objects, 
    // five rows each, and add to DataTable.
    for(int i = 0; i <= 4; i ++)
    {
        row = table.NewRow();
        row["childID"] = i;
        row["ChildItem"] = "Item " + i;
        row["ParentID"] = 0 ;
        table.Rows.Add(row);
    }
    for(int i = 0; i <= 4; i ++)
    {
        row = table.NewRow();
        row["childID"] = i + 5;
        row["ChildItem"] = "Item " + i;
        row["ParentID"] = 1 ;
        table.Rows.Add(row);
    }
    for(int i = 0; i <= 4; i ++)
    {
        row = table.NewRow();
        row["childID"] = i + 10;
        row["ChildItem"] = "Item " + i;
        row["ParentID"] = 2 ;
        table.Rows.Add(row);
    }
}

private void MakeDataRelation()
{
    // DataRelation requires two DataColumn 
    // (parent and child) and a name.
    DataColumn parentColumn = 
        dataSet.Tables["ParentTable"].Columns["id"];
    DataColumn childColumn = 
        dataSet.Tables["ChildTable"].Columns["ParentID"];
    DataRelation relation = new 
        DataRelation("parent2Child", parentColumn, childColumn);
    dataSet.Tables["ChildTable"].ParentRelations.Add(relation);
}

private void BindToDataGrid()
{
    // Instruct the DataGrid to bind to the DataSet, with the 
    // ParentTable as the topmost DataTable.
    dataGrid1.SetDataBinding(dataSet,"ParentTable");
}

[热学沸腾56]

学习，up

[qq2013]

[Quote=引用 3 楼 huwuling922 的回复:]
学习，up
[/Quote]
up

[lanxingxing]

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[沐雪架构师]

能来些中文吗？ 我们是中国人，时时不忘我们的文字！！
[Quote=引用 2 楼 liuyeede 的回复:]
下面的代码出自msdn：
C# codeprivate System.Data.DataSet dataSet;privatevoid MakeDataTables()
{// Run all of the functions. MakeParentTable();
MakeChildTable();
MakeDataRelation();
BindToDataGrid();
}privatevoid MakeParentTable()
{// Create a new DataTable. System.Data.DataTable table=new DataTable("ParentTable");// Declare variables for DataColumn and DataRow objects. DataColumn column;
DataRow row;// Create new DataColumn, set DataType,// ColumnName and add to DataTable. column=new DataColumn();
column.DataType= System.Type.GetType("System.Int32");
column.ColumnName="id";
column.ReadOnly=true;
column.Unique=true;// Add the Column to the DataColumnCollection. table.Columns.Add(column);// Create second column. column=new DataColumn();
column.DataType= System.Type.GetType("System.String");
column.ColumnName="ParentItem";
column.AutoIncrement=false;
column.Caption="ParentItem";
column.ReadOnly=false;
column.Unique=false;// Add the column to the table. table.Columns.Add(column);// Make the ID column the primary key column. DataColumn[] PrimaryKeyColumns=new DataColumn[1];
PrimaryKeyColumns[0]= table.Columns["id"];
table.PrimaryKey= PrimaryKeyColumns;// Instantiate the DataSet variable. dataSet=new DataSet();// Add the new DataTable to the DataSet. dataSet.Tables.Add(table);// Create three new DataRow objects and add// them to the DataTablefor (int i=0; i<=2; i++)
{
row= table.NewRow();
row["id"]= i;
row["ParentItem"]="ParentItem"+ i;
table.Rows.Add(row);
}
}privatevoid MakeChildTable()
{// Create a new DataTable. DataTable table=new DataTable("childTable");
DataColumn column;
DataRow row;// Create first column and add to the DataTable. column=new DataColumn();
column.DataType= System.Type.GetType("System.Int32");
column.ColumnName="ChildID";
column.AutoIncrement=true;
column.Caption="ID";
column.ReadOnly=true;
column.Unique=true;// Add the column to the DataColumnCollection. table.Columns.Add(column);// Create second column. column=new DataColumn();
column.DataType= System.Type.GetType("System.String");
column.ColumnName="ChildItem";
column.AutoIncrement=false;
column.Caption="ChildItem";
column.ReadOnly=false;
column.Unique=false;
table.Columns.Add(column);// Create third column. column=new DataColumn();
column.DataType= System.Type.GetType("System.Int32");
column.ColumnName="ParentID";
column.AutoIncrement=false;
column.Caption="ParentID";
column.ReadOnly=false;
column.Unique=false;
table.Columns.Add(column);

dataSet.Tables.Add(table);// Create three sets of DataRow objects,// five rows each, and add to DataTable.for(int i=0; i<=4; i++)
{
row= table.NewRow();
row["childID"]= i;
row["ChildItem"]="Item"+ i;
row["ParentID"]=0 ;
table.Rows.Add(row);
}for(int i=0; i<=4; i++)
{
row= table.NewRow();
row["childID"]= i+5;
row["ChildItem"]="Item"+ i;
row["ParentID"]=1 ;
table.Rows.Add(row);
}for(int i=0; i<=4; i++)
{
row= table.NewRow();
row["childID"]= i+10;
row["ChildItem"]="Item"+ i;
row["ParentID"]=2 ;
table.Rows.Add(row);
}
}privatevoid MakeDataRelation()
{// DataRelation requires two DataColumn// (parent and child) and a name. DataColumn parentColumn=
dataSet.Tables["ParentTable"].Columns["id"];
DataColumn childColumn=
dataSet.Tables["ChildTable"].Columns["ParentID"];
DataRelation relation=new
DataRelation("parent2Child", parentColumn, childColumn);
dataSet.Tables["ChildTable"].ParentRelations.Add(relation);
}privatevoid BindToDataGrid()
{// Instruct the DataGrid to bind to the DataSet, with the// ParentTable as the topmost DataTable. dataGrid1.SetDataBinding(dataSet,"ParentTable");
}
[/Quote]