How to set max byte length of datagridview when paste

问题

I have a datagridview where DataNames can be entered in a textbox column.I restrict the input length of this column to 6 characters by using the MaxInputLength property of the DataGridViewTextBoxColumn.

Here, I want to explain my problem step by step.
1. I wrote Double Byte Characters(eg.１２３４５６７８９０) on a notepad and copy it.Then I went to this DataGridViewTextBox ,Right Click and then choosed Paste.The DataGridViewTextBox showed １２３４５６.
2.I wrote Double Byte Characters(eg.１２３４５６) on a notepad and copy it.Then I went to this DataGridViewTextBox ,Right Click and then choosed Paste.The DataGridViewTextBox showed １２３４５６.
So,MaxInputLength property only restrict to the input character length( not caring single byte or double byte).

I want to show only １２３(6 bytes).
Is there a property or a way to restrict the byte character length especially in Paste operation?

Thanks in advance.

回答1:

I guess you could just handle it in the TextChangedEvent

Something like:

private void textBox1_TextChanged(object sender, EventArgs e)
{
    var textBytes = Encoding.UTF8.GetBytes(textBox1.Text);
    var textByteCount = Encoding.UTF8.GetByteCount(textBox1.Text);
    var textCharCount = Encoding.UTF8.GetCharCount(textBytes);

    if (textCharCount != textByteCount && textByteCount >= 12)
    {
        textBox1.Text = Encoding.UTF32.GetString(Encoding.UTF32.GetBytes(textBox1.Text), 0, 12);
    }
    else if (textBox1.Text.Length >= 6)
    {
        textBox1.Text = textBox1.Text.Substring(0, 6);
    }
}  

来源：https://stackoverflow.com/questions/14888488/how-to-set-max-byte-length-of-datagridview-when-paste