在现有数据表中插入一行

Question

我尝试了一个问题的方法。

public DataTable allSupportPoints(DataTable createPath, double rMax, double interval, int curveType)
    {
        List <DataTable> theCornerCurves = cornerCurves(createPath, rMax, interval, curveType);
        DataTable curvePoints = CustomMerge(theCornerCurves);

        double X1 = Convert.ToDouble(createPath.Rows[0][1]);
        double Y1 = Convert.ToDouble(createPath.Rows[0][2]);
        double X2, Y2;
        int count = curvePoints.Rows.Count;
        double theDistance;
        int pointInsert;
        for (int i = 0; i < count;)
        {
            X2 = Convert.ToDouble(theCornerCurves[i].Rows[0][0]);
            Y2 = Convert.ToDouble(theCornerCurves[i].Rows[0][0]);
            theDistance = distance(X1,Y1,X2,Y2);
            int j=0;
            if ( theDistance> interval)
            {
                pointInsert = Convert.ToInt32 (theDistance / interval);
                DataTable temp = straightLineGenerator(X1, Y1, X2, Y2,interval);
                for (j = 0; j < temp.Rows.Count; j++)
                {
                    var rowTemp = temp.NewRow(); 
                    rowTemp.ItemArray =    temp.Rows[j].ItemArray.Clone() as object[];
                    curvePoints.Rows.InsertAt(rowTemp, i + j);
                }
            }
            X1=Convert.ToDouble(curvePoints.Rows[i+j][0]);
            Y1 = 0;
            count = curvePoints.Rows.Count;
            i = i + 1;
        }
        return curvePoints;

    }

我收到此运行时错误：此行已属于另一个 table。我尝试了不同的插入方法，但错误是一样的，我也参考了一些帖子，但它似乎不起作用请帮忙!!!!

Answer 1

改变这个：

var rowTemp = temp.NewRow();

对此：

var rowTemp = curvePoints.NewRow();

事实上，该行必须由您要添加的 table 创建

Answer 2

您的这部分代码：

for (j = 0; j < temp.Rows.Count; j++)
{
    var rowTemp = temp.NewRow(); 
    rowTemp.ItemArray = temp.Rows[j].ItemArray.Clone() as object[];
    curvePoints.Rows.InsertAt(rowTemp, i + j);
}

不正确。首先，您要向 temp 添加新行，然后尝试将其插入 curvePoints。因为它已经属于 temp 数据表 - 你得到了你提到的异常。

这段代码可以简化为

for (j = 0; j < temp.Rows.Count; j++)
    curvePoints.ImportRow(temp.Rows[j]);

但请注意：ImportRow 在最后位置插入行，因此如果您真的需要像您正在做的那样将行插入特定位置 - 只需保持代码不变，只更改 var rowTemp = temp.NewRow();至 var rowTemp = curvePoints.NewRow();

在现有数据表中插入一行

Insert a Row in Existing DataTable

c#

datatable