ASP.Net/Language Basics/Type Convert
Содержание
- 1 Convert date to string (C#)
- 2 Convert double and date to string (C#)
- 3 Convert int to String (C#)
- 4 Convert int value to string (VB.net)
- 5 Convert Now (current date) to string (C#)
- 6 Welcome
- 6.1 Convert selected date from asp:Calendar to long string (VB.net)
- 6.2 Convert string to double (VB.net)
- 6.3 Convert String to int and decimal (C#)
- 6.4 Convert value from asp:TextBox to int and compare (VB.net)
- 6.5 Convert value in asp:TextBox to bool in try catch block (VB.net)
- 6.6 Convert value in asp:TextBox to date in try catch block (VB.net)
- 6.7 Convert value in asp:TextBox to int in try catch block (VB.net)
- 6.8 Int, String and date variables (C#)
- 6.9 Output ASCII Code (C#)
- 6.10 Read string from asp textbox and format it to DateTime (C#)
Convert date to string (C#)
<source lang="csharp">
<script Language="c#" runat="server"> void Page_Load() {
string strEarn = "150";
string strTax = "23.0";
double dblEarn = Convert.ToInt32(strEarn);
decimal decTax = Convert.ToDecimal(strTax);
double dblTotal = dblEarn - ((dblEarn/100) * (double)decTax);
Display1.Text = dblTotal.ToString();
DateTime datNow = DateTime.Now;
Display2.Text = " " + datNow.ToString("d");
} </script> <html> <head>
<title>Declaring Variables</title>
</head> <body>
Your total earnings after tax are $ <asp:label id="Display1" runat="server" />
The date is <asp:label id="Display2" runat="server" />
</body> </html>
</source>
Convert double and date to string (C#)
<source lang="csharp">
<script Language="c#" runat="server"> void Page_Load() {
string strEarn = "150";
string strTax = "23.0";
double dblEarn = Convert.ToInt32(strEarn);
decimal decTax = Convert.ToDecimal(strTax);
double dblTotal = dblEarn - ((dblEarn/100) * (double)decTax);
Display1.Text = dblTotal.ToString();
DateTime datNow = DateTime.Now;
Display2.Text = " " + datNow.ToString("d");
} </script> <html> <head>
<title>Declaring Variables</title>
</head> <body>
<asp:label id="Display1" runat="server" />
<asp:label id="Display2" runat="server" />
</body> </html>
</source>
Convert int to String (C#)
<source lang="csharp">
<%@ Page Language="c#" %> <script runat="server"> void Page_Load() {
const int AbsoluteZero = -273; lblOut.Text = Convert.ToString(AbsoluteZero);
} </script> <html> <head> <title>Creating Variables Example</title> </head> <body>
<asp:Label runat="server" ID="lblOut"/>
</body> </html>
</source>
Convert int value to string (VB.net)
<source lang="csharp">
<script runat="Server" language="VB"> Sub Page_Load()
Dim strArrayDetails(2) As String Dim intLoop As Integer strArrayDetails(0) = text1.Text strArrayDetails(1) = text2.Text strArrayDetails(2) = text3.Text Message1.text = CStr(strArrayDetails(0)) Message2.text = CStr(strArrayDetails(1)) Message3.text = CStr(strArrayDetails(2))
End Sub </script> <html>
<head> <title>Text Box Example</title> </head> <body> <asp:label id="message1" runat="server" />
<asp:label id="message2" runat="server" />
<asp:label id="message3" runat="server" />
<form runat="server"> Please enter your name: <asp:textbox id="text1" runat="server" />
Please enter your address: <asp:textbox id="text2" runat="server" rows=5 textmode="multiline" />
Please enter your chosen password: <asp:textbox id="text3" runat="server" textmode="password" />
<input type="Submit"> </form> </body>
</html>
</source>
Convert Now (current date) to string (C#)
<source lang="csharp">
<script language="c#" runat="server"> void Page_Load() {
time.Text=DateTime.Now.Hour.ToString() + ":" +
DateTime.Now.Minute.ToString() + ":" +
DateTime.Now.Second.ToString();
} </script> <html> <head><title>The Punctual Web Server</title></head> <body>
Welcome
In WebServerLand the time is currently:
<asp:label id="time" runat="server" /> </body> </html>
</source>
Convert selected date from asp:Calendar to long string (VB.net)
<source lang="csharp">
<%@ Page Language="VB" %> <script runat="server">
Sub Button1_Click(sender As Object, e As EventArgs)
Label1.Text = Calendar1.SelectedDate.ToLongDateString()
End Sub
</script> <html> <head> </head> <body>
<form runat="server">
<asp:Calendar id="Calendar1" runat="server"></asp:Calendar>
<asp:Button id="Button1" onclick="Button1_Click" runat="server" Text="Button"></asp:Button>
<asp:Label id="Label1" runat="server">Label</asp:Label>
</form>
</body> </html>
</source>
Convert string to double (VB.net)
<source lang="csharp">
<%@ page language="vb" runat="server" %> <script runat="server">
Sub Page_Load() pi.text = Math.PI exp.text = Math.E End Sub Sub Update(Sender As Object, E As EventArgs) Dim dblInput As Double = CDbl(input.text) sqrt_input.text = dblInput sqrt_result.text = Math.Sqrt(dblInput) abs_input.text = dblInput abs_result.text = Math.Abs(dblInput) log_input.text = dblInput log_result.text = Math.Log10(dblInput) End Sub
</script> <html>
<body>
Pi = <asp:label id="pi" runat="server" />
Exponential Constant = <asp:label id="exp" runat="server" />
<form runat="server"> Input = <asp:textbox id="input" runat="server" /> <asp:button text="Submit" runat="server" onclick="update" /></form>
Square root of <asp:label id="sqrt_input" runat="server"/> = <asp:label id="sqrt_result" runat="server" />
Absolute Value of <asp:label id="abs_input" runat="server"/> = <asp:label id="abs_result" runat="server" />
Logarithm of <asp:label id="log_input" runat="server"/> = <asp:label id="log_result" runat="server" />
</body>
</html>
</source>
Convert String to int and decimal (C#)
<source lang="csharp">
<script Language="c#" runat="server"> void Page_Load() {
string strEarn = "150";
string strTax = "23.0";
double dblEarn = Convert.ToInt32(strEarn);
decimal decTax = Convert.ToDecimal(strTax);
double dblTotal = dblEarn - ((dblEarn/100) * (double)decTax);
Display1.Text = dblTotal.ToString();
DateTime datNow = DateTime.Now;
Display2.Text = " " + datNow.ToString("d");
} </script> <html> <head>
<title>Declaring Variables</title>
</head> <body>
<asp:label id="Display1" runat="server" />
<asp:label id="Display2" runat="server" />
</body> </html>
</source>
Convert value from asp:TextBox to int and compare (VB.net)
<source lang="csharp">
<%@ Page Language="VB" %> <script runat="server">
Sub Reset()
Textbox1.Text = ""
Textbox2.Text = "0"
End Sub
Sub Page_Load(sender As Object, e As EventArgs)
If Not Page.IsPostback
Reset()
End If
End Sub
Sub btnSubmit_Click(sender As Object, e As EventArgs)
If cint(textbox2.text) < 20 Then
label1.text = "Hi " & textbox1.text & ", you are " & textbox2.text & ", which is young!"
Else If cint(textbox2.text) < 40 Then
label1.text = "Hi " & textbox1.text & ", you are " & textbox2.text & ", which means you"re middle-aged!"
Else
label1.text = "Hi " & textbox1.text & ", you"re old!"
End If
End Sub
Sub btnReset_Click(sender As Object, e As EventArgs)
Reset()
End Sub
</script> <html> <head> </head> <body>
<form runat="server">
Enter your name: <asp:TextBox id="TextBox1" runat="server"></asp:TextBox>
Enter you age: <asp:TextBox id="TextBox2" runat="server"></asp:TextBox>
<asp:Button id="btnSubmit" onclick="btnSubmit_Click" runat="server" Text="Submit"></asp:Button> <asp:Button id="btnReset" onclick="btnReset_Click" runat="server" Text="Reset"></asp:Button>
<asp:Label id="Label1" runat="server"></asp:Label>
</form>
</body> </html>
</source>
Convert value in asp:TextBox to bool in try catch block (VB.net)
<source lang="csharp">
<%@ Page Language="VB" %> <script runat="server">
Sub btnConvert_Click(sender As Object, e As EventArgs)
Try
lblToInt.Text = cint(txtValueToConvert.Text)
Catch
lblToInt.Text = "Could not convert to Integer"
End Try
Try
lblToDateTime.Text = cdate(txtValueToConvert.Text)
Catch
lblToDateTime.Text = "Could not convert to Date/Time"
End Try
Try
lblToBoolean.Text = cbool(txtValueToConvert.Text)
Catch
lblToBoolean.Text = "Could not convert to Boolean"
End Try
End Sub
</script> <html> <head> </head> <body>
<form runat="server">
Original input: <asp:TextBox id="txtValueToConvert" runat="server"></asp:TextBox> <asp:Button id="btnConvert" onclick="btnConvert_Click" runat="server" Text="Convert!"></asp:Button>
Convert to Integer produces: <asp:Label id="lblToInt" runat="server"></asp:Label>
Convert to Date/Time produces: <asp:Label id="lblToDateTime" runat="server"></asp:Label>
Convert to Boolean produces: <asp:Label id="lblToBoolean" runat="server"></asp:Label>
</form>
</body> </html>
</source>
Convert value in asp:TextBox to date in try catch block (VB.net)
<source lang="csharp">
<%@ Page Language="VB" %> <script runat="server">
Sub btnConvert_Click(sender As Object, e As EventArgs)
Try
lblToInt.Text = cint(txtValueToConvert.Text)
Catch
lblToInt.Text = "Could not convert to Integer"
End Try
Try
lblToDateTime.Text = cdate(txtValueToConvert.Text)
Catch
lblToDateTime.Text = "Could not convert to Date/Time"
End Try
Try
lblToBoolean.Text = cbool(txtValueToConvert.Text)
Catch
lblToBoolean.Text = "Could not convert to Boolean"
End Try
End Sub
</script> <html> <head> </head> <body>
<form runat="server">
Original input: <asp:TextBox id="txtValueToConvert" runat="server"></asp:TextBox> <asp:Button id="btnConvert" onclick="btnConvert_Click" runat="server" Text="Convert!"></asp:Button>
Convert to Integer produces: <asp:Label id="lblToInt" runat="server"></asp:Label>
Convert to Date/Time produces: <asp:Label id="lblToDateTime" runat="server"></asp:Label>
Convert to Boolean produces: <asp:Label id="lblToBoolean" runat="server"></asp:Label>
</form>
</body> </html>
</source>
Convert value in asp:TextBox to int in try catch block (VB.net)
<source lang="csharp">
<%@ Page Language="VB" %> <script runat="server">
Sub btnConvert_Click(sender As Object, e As EventArgs)
Try
lblToInt.Text = cint(txtValueToConvert.Text)
Catch
lblToInt.Text = "Could not convert to Integer"
End Try
Try
lblToDateTime.Text = cdate(txtValueToConvert.Text)
Catch
lblToDateTime.Text = "Could not convert to Date/Time"
End Try
Try
lblToBoolean.Text = cbool(txtValueToConvert.Text)
Catch
lblToBoolean.Text = "Could not convert to Boolean"
End Try
End Sub
</script> <html> <head> </head> <body>
<form runat="server">
Original input: <asp:TextBox id="txtValueToConvert" runat="server"></asp:TextBox> <asp:Button id="btnConvert" onclick="btnConvert_Click" runat="server" Text="Convert!"></asp:Button>
Convert to Integer produces: <asp:Label id="lblToInt" runat="server"></asp:Label>
Convert to Date/Time produces: <asp:Label id="lblToDateTime" runat="server"></asp:Label>
Convert to Boolean produces: <asp:Label id="lblToBoolean" runat="server"></asp:Label>
</form>
</body> </html>
</source>
Int, String and date variables (C#)
<source lang="csharp">
<%@ Page Language="C#" Debug="true" %> <script runat="server">
void Page_Load()
{
string CapitalCityOfUK;
int NumberOfStates;
DateTime IndependenceDay;
CapitalCityOfUK = "London";
NumberOfStates = 50;
IndependenceDay = Convert.ToDateTime("7/4/1776");
lblCapital.Text = CapitalCityOfUK;
lblNumStates.Text = Convert.ToString(NumberOfStates);
lblDateIndependence.Text = Convert.ToString(IndependenceDay);
}
</script> <html> <head>
<title>Creating Variables Example</title>
</head> <body>
The contents of CapitalCityOfUk is: <asp:Label id="lblCapital" runat="server"></asp:Label>
The contents of NumberOfStates is: <asp:Label id="lblNumStates" runat="server"></asp:Label>
The contents of IndependenceDay is: <asp:Label id="lblDateIndependence" runat="server"></asp:Label>
</body> </html>
</source>
Output ASCII Code (C#)
<source lang="csharp">
<%@ Page Language="C#" Debug="true" %> <script runat="server">
void Page_Load()
{
lblASCII.Text += "| Character | ASCII code |
| " + Convert.ToChar(bytCounter) + " | " + Convert.ToString(bytCounter) + " |
}
</script> <html> <head>
<title>Demonstrate String Comparison</title>
</head> <body>
<form runat="server">
For your reference, here are the ASCII codes:
<asp:Label id="lblASCII" runat="server"></asp:Label>
</form>
</body> </html>
</source>
Read string from asp textbox and format it to DateTime (C#)
<source lang="csharp">
<%@ Page Language="C#" Debug="true"%> <script runat="server">
void Page_Load()
{
if (Page.IsPostBack)
{
DateTime MyDateTime;
lblDateOut.Text = Convert.ToString(txtDateIn.Text); //reads the variable
}
}
</script>
<html>
<head>
<title>Variables Example - String and Char</title>
</head>
<body>
<form runat="server">
<asp:TextBox runat="server" ID="txtDateIn" ></asp:TextBox>
<asp:Label runat="server" ID="lblDateOut" >Label</asp:Label>
<asp:Button runat="server" Text="Click me format date time"></asp:Button>
</form>
</body>
</html>
</source>
