TextBox.Focus

In Windows Forms, only some controls can receive input and, of those which can, only one control can receive input at any one time.

The Control.Focus() method moves the input focus to the control on which it's called.

So textBox1.Focus() moves the input focus to textBox1.

This is particularly useful when you're checking whether a textbox's input is valid or not and, if it's not, moving the focus back to the textbox so the user can correct it.

If, for example you only want a textbox to receive numeric input, ytou could do this:

private void textBox1_Leave(object sender, System.EventArgs e)

{

double d;

if(!Double,TryParse(textBox1.Text, out d))

{

MessageBox.Show("The input is not a number. Please amend");

textBox1.Focus();

return;

}

// do something with 'd'

}

One function common to most all node types is focus, which gives keyboard focus to the corresponding element. The focus function is commonly used in data entry forms, search pages, and login screens to put the user's keyboard cursor in a particular textbox when the web page loads so that the user can start typing in his search query or username without having to first click the textbox with his mouse. Another useful function is select, which is available for and

<span style="color: #000000;"> elements and selects the contents of the textbox.<br /><br />Ex:<br /></span>public partial class Form1 : Form<br />{<br />public Form1()<br />{<br />InitializeComponent();<br />textBox1.Select();<br />}<br /><br /><br />Thanks<br /><a href="http://www.jobpencil.com/" target="_self" title="Find IT Jobs">Find Jobs</a></div><div class="comment-foot"></div></div></article></li><li class="comment-thread"><article class="comment"><a class="comment-photo-link" href="/members/munesh-sharma4" title="Munesh Sharma"><img class="comment-photo" src="https://cdn.c-sharpcorner.com/uploadfile/authorimage/5d065a20150927023141.webp" alt="Munesh Sharma" title="Munesh Sharma" loading="lazy" data-avatar-name="Munesh Sharma" referrerPolicy="no-referrer"/></a><div class="comment-main"><div class="comment-head"><p class="comment-byline"><a href="/members/munesh-sharma4" class="comment-author">Munesh Sharma</a><span class="posted-when" tabindex="0"><time class="posted-when-value comment-time" dateTime="2014-04-11T06:39:30.133Z">12y ago</time><span class="posted-when-pop" role="tooltip"><span>Posted Apr 11, 2014, 6:39 AM</span></span></span></p></div><div class="article-body">textbox.focus();<br /><br />this property is used to show which textbox we have to fill.<br /><br />suppose when open Facebook then at "username, textbox" already there is focused means it suggest to fill it.. try it then u will understand better.</div><div class="comment-foot"></div></div></article></li></ul></section></div></div><script>$RS=function(a,b){a=document.getElementById(a);b=document.getElementById(b);for(a.parentNode.removeChild(a);a.firstChild;)b.parentNode.insertBefore(a.firstChild,b);b.parentNode.removeChild(b)};$RS("S:2","P:2")</script><script>$RB=[];$RV=function(a){$RT=performance.now();for(var b=0;b<a.length;b+=2){var c=a[b],e=a[b+1];null!==e.parentNode&&e.parentNode.removeChild(e);var f=c.parentNode;if(f){var g=c.previousSibling,h=0;do{if(c&&8===c.nodeType){var d=c.data;if("/$"===d||"/&"===d)if(0===h)break;else h--;else"$"!==d&&"$?"!==d&&"$~"!==d&&"$!"!==d&&"&"!==d||h++}d=c.nextSibling;f.removeChild(c);c=d}while(c);for(;e.firstChild;)f.insertBefore(e.firstChild,c);g.data="$";g._reactRetry&&requestAnimationFrame(g._reactRetry)}}a.length=0};
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8 Replies

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Joe Wilson12y ago
Thank you very Much.
Vulpes12y ago
Yes, it moves the input focus to the textbox so that you can edit its contents.
Joe Wilson12y ago
You mean it lets me edit what is in the text box , doesn't it?
Vulpes12y ago
In Windows Forms, only some controls can receive input and, of those which can, only one control can receive input at any one time.

The Control.Focus() method moves the input focus to the control on which it's called.

So textBox1.Focus() moves the input focus to textBox1.

This is particularly useful when you're checking whether a textbox's input is valid or not and, if it's not, moving the focus back to the textbox so the user can correct it.

If, for example you only want a textbox to receive numeric input, ytou could do this:

private void textBox1_Leave(object sender, System.EventArgs e)
{
double d;
if(!Double,TryParse(textBox1.Text, out d))
{
MessageBox.Show("The input is not a number. Please amend");
textBox1.Focus();
return;
}

// do something with 'd'
}
Joe Wilson12y ago
Your answer didn't help me at all.
Abhay Shanker12y ago
This Property tells about the textbox which is to be focused.
JobPencil12y ago
One function common to most all node types is focus, which gives keyboard focus to the corresponding element. The focus function is commonly used in data entry forms, search pages, and login screens to put the user's keyboard cursor in a particular textbox when the web page loads so that the user can start typing in his search query or username without having to first click the textbox with his mouse. Another useful function is select, which is available for and <span style="color: #000000;"> elements and selects the contents of the textbox.<br /><br />Ex:<br /></span>public partial class Form1 : Form<br />{<br />public Form1()<br />{<br />InitializeComponent();<br />textBox1.Select();<br />}<br /><br /><br />Thanks<br /><a href="http://www.jobpencil.com/" target="_self" title="Find IT Jobs">Find Jobs</a></div><div class="comment-foot"></div></div></article></li><li class="comment-thread"><article class="comment"><a class="comment-photo-link" href="/members/munesh-sharma4" title="Munesh Sharma"><img class="comment-photo" src="https://cdn.c-sharpcorner.com/uploadfile/authorimage/5d065a20150927023141.webp" alt="Munesh Sharma" title="Munesh Sharma" loading="lazy" data-avatar-name="Munesh Sharma" referrerPolicy="no-referrer"/></a><div class="comment-main"><div class="comment-head"><p class="comment-byline"><a href="/members/munesh-sharma4" class="comment-author">Munesh Sharma</a><span class="posted-when" tabindex="0"><time class="posted-when-value comment-time" dateTime="2014-04-11T06:39:30.133Z">12y ago</time><span class="posted-when-pop" role="tooltip"><span>Posted Apr 11, 2014, 6:39 AM</span></span></span></p></div><div class="article-body">textbox.focus();<br /><br />this property is used to show which textbox we have to fill.<br /><br />suppose when open Facebook then at "username, textbox" already there is focused means it suggest to fill it.. try it then u will understand better.</div><div class="comment-foot"></div></div></article></li></ul></section></div></div><script>$RS=function(a,b){a=document.getElementById(a);b=document.getElementById(b);for(a.parentNode.removeChild(a);a.firstChild;)b.parentNode.insertBefore(a.firstChild,b);b.parentNode.removeChild(b)};$RS("S:2","P:2")</script><script>$RB=[];$RV=function(a){$RT=performance.now();for(var b=0;b<a.length;b+=2){var c=a[b],e=a[b+1];null!==e.parentNode&&e.parentNode.removeChild(e);var f=c.parentNode;if(f){var g=c.previousSibling,h=0;do{if(c&&8===c.nodeType){var d=c.data;if("/$"===d||"/&"===d)if(0===h)break;else h--;else"$"!==d&&"$?"!==d&&"$~"!==d&&"$!"!==d&&"&"!==d||h++}d=c.nextSibling;f.removeChild(c);c=d}while(c);for(;e.firstChild;)f.insertBefore(e.firstChild,c);g.data="$";g._reactRetry&&requestAnimationFrame(g._reactRetry)}}a.length=0}; $RC=function(a,b){if(b=document.getElementById(b))(a=document.getElementById(a))?(a.previousSibling.data="$~",$RB.push(a,b),2===$RB.length&&("number"!==typeof $RT?requestAnimationFrame($RV.bind(null,$RB)):(a=performance.now(),setTimeout($RV.bind(null,$RB),2300>a&&2E3<a?2300-a:$RT+300-a)))):b.parentNode.removeChild(b)};$RC("B:1","S:1")</script><div style="display:none" id="S:3"></div><script>$RC("B:3","S:3")</script><div style="display:none" id="S:0"></div><script>$RC("B:0","S:0")</script></body></html>