C# 是否可以在不覆盖文本框的第一个输入值的情况下在一个文本框中获取两个输入文本框值？

Question

I've been searching this for a while but i didn't get any information about this, so i don't know if it is possible or not. Here's what i'm trying to achieve. Any suggestions there ? Thank you

Example:

• Textbox 1 input value is: HELLO and Textbox 2 input value is: WORLD
• GET the first 3 letters of HELLO: HEL (using substring)
• Textbox 3 will get HEL so the input value is : HEL
• Now is it possible to get the textbox 2 value without overwriting the first one? expected output: HELWORLD

Answer 1

当然，这是可能的：

Textbox3.Text = Textbox1.Text.Substring(0,3)+Textbox2.Text

Answer 2

Another way to do it if there's a possibility that textBox1.Text is less than 3 characters is to use the Take method to take up to 3 characters from the string (treating is as an array of characters), then use Concat to put those characters back into a string, and finally concatenate it with textBox2.Text .

textBox3.Text = string.Concat(textBox1.Text.Take(3)) + textBox2.Text;

It's a little "wordy", but will prevent exceptions from being thrown if textBox1 contains fewer than 3 characters.

Answer 3

sure it is possible. Just take care that the textbox has some string longer than 3 characters

string processedText;
            int NoOfChars = 3;
            if (textBox1.Text.Length >= NoOfChars)
                processedText = textBox1.Text.Substring(0, NoOfChars);
            else
                processedText = textBox1.Text;

            textBox3.Text = processedText + textBox2.Text

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