How to check whether the textbox have only numbers.

The following code sample shows how to check whether the textbox have only numbers.
int a=0;
foreach(string s in textbox1.text)
if ((s>65 && s<90) || (s>97 && s<122))
{"Characters are not allowed");
//using the ascii values we checking whether the values present in the textbox is character or numbers.


Author: kingfisher12 May 2008 Member Level: Gold   Points : 2

CHNumeric = IsNumeric(txtbox1.Text)
If CHNumeric = False Then
MsgBox("Enter numeric value Only", MsgBoxStyle.Exclamation, Application.ProductName)
Exit Sub
End If

'----------> I have used an inbuilt function "IsNumeric" which returns boolean value after checking for numeric values

Author: santhoshkumar23 May 2008 Member Level: Gold   Points : 2

By default the textbox value is string right, then how can v check isNumeric for string value.

Author: santhoshkumar04 Jun 2008 Member Level: Gold   Points : 0

ok. thank you ranipriya

Author: sivangari11 Jun 2008 Member Level: Gold   Points : 2

protected void Button1_Click(object sender, EventArgs e)
string str = TextBox1.Text;
string str1 = TextBox4.Text;

int result = 0;
if( (int.TryParse(str, System.Globalization.NumberStyles.Integer, System.Globalization.NumberFormatInfo.CurrentInfo, out result)) && (int.TryParse(str1, System.Globalization.NumberStyles.Integer, System.Globalization.NumberFormatInfo.CurrentInfo, out result)))
Label1.Text = "Number";
Label1.Text = "string";

Author: KR12 Dec 2008 Member Level: Gold   Points : 1

Find the below code,

private void button1_Click(object sender, EventArgs e)
int s;
if (!int.TryParse(textBox1.Text, out s))
MessageBox.Show("Charactes not allowed");

Author: Abhinav Misra14 Dec 2008 Member Level: Silver   Points : 1

dont u think that it is better to use

java script or compare validation control and set its property
for type check

Author: Radhu07 Aug 2009 Member Level: Gold   Points : 2

//this will enable user to enter only numeric values

function EnableKeys()

var keyCode = event.keyCode;

//Enable Only numeric values

if(keyCode>=48 && keyCode<=57 )
event.returnValue = true;
event.returnValue = false;

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