对代码进行一些更改

Make a little change in your code

dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;

并且在GridView1_CellStateChanged事件中没有直接应用此

and in the GridView1_CellStateChanged event without directly applying this

SplitMethod.ReadOnly = true;// it will always make the whole column readonly

尝试使用这个

try using this

dataGridView1.CurrentRow.Cells[i].ReadOnly = true;//i is the column index of the combobox column

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