Question: Best way to handle DBNULL in datareaders

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  1. Ravikanth[MVP] #1

    Default Question: Best way to handle DBNULL in datareaders

    Hi

    Alternative is check before assigning as TextBox value.

    TextBox1.Text =myRow["ColumnName"]==DBNull.Value)?"":
    (string)myRow["ColumnName"]

    HTH
    Ravikanth

    >-----Original Message-----
    >Im looking for the best way to handle DBNULL's in
    datareaders.
    >
    >In a project im currently working on im using a lot of
    optional data with
    >datareaders.
    >
    >Using the following syntax im getting errors when the
    field contains a
    >DBNULL value
    >Textbox1.text = myreader(1)
    >
    >My current solution for this is using the isnull
    function of MSSQL and
    >substituting null's with "" there. This means a lot of
    typing for me, which
    >is never a good thing.
    >
    >Does anyone have a better solution to my problem?
    >
    >
    >.
    >
    Ravikanth[MVP] Guest
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  2. Aemca #2

    Default Re: Question: Best way to handle DBNULL in datareaders

    That was my first solution but thats way 2 much work to type that for each
    value i want to use.

    So this is not really a better solution for me.

    > Hi
    >
    > Alternative is check before assigning as TextBox value.
    >
    > TextBox1.Text =myRow["ColumnName"]==DBNull.Value)?"":
    > (string)myRow["ColumnName"]
    >
    > HTH
    > Ravikanth
    >
    >
    > >-----Original Message-----
    > >Im looking for the best way to handle DBNULL's in
    > datareaders.
    > >
    > >In a project im currently working on im using a lot of
    > optional data with
    > >datareaders.
    > >
    > >Using the following syntax im getting errors when the
    > field contains a
    > >DBNULL value
    > >Textbox1.text = myreader(1)
    > >
    > >My current solution for this is using the isnull
    > function of MSSQL and
    > >substituting null's with "" there. This means a lot of
    > typing for me, which
    > >is never a good thing.
    > >
    > >Does anyone have a better solution to my problem?
    > >
    > >
    > >.
    > >

    Aemca Guest
    Reply With Quote Reply With Quote
  3. #3

    Default Re: Question: Best way to handle DBNULL in datareaders

    You could make a function which wraps the null and put that in...

    Textbox1.text = CleanThis(myreader(1))

    Have you tried adding the null to an empty string?

    Textbox1.text = "" & myreader(1)

    or something like that

    It's not clear if you are using getstring or getvalue or what

    ....?

    "Aemca" <none@none.com> wrote in message
    news:eCQJpFGTDHA.2852@tk2msftngp13.phx.gbl...
    > That was my first solution but thats way 2 much work to type that for each
    > value i want to use.
    >
    > So this is not really a better solution for me.
    >
    >
    > > Hi
    > >
    > > Alternative is check before assigning as TextBox value.
    > >
    > > TextBox1.Text =myRow["ColumnName"]==DBNull.Value)?"":
    > > (string)myRow["ColumnName"]
    > >
    > > HTH
    > > Ravikanth
    > >
    > >
    > > >-----Original Message-----
    > > >Im looking for the best way to handle DBNULL's in
    > > datareaders.
    > > >
    > > >In a project im currently working on im using a lot of
    > > optional data with
    > > >datareaders.
    > > >
    > > >Using the following syntax im getting errors when the
    > > field contains a
    > > >DBNULL value
    > > >Textbox1.text = myreader(1)
    > > >
    > > >My current solution for this is using the isnull
    > > function of MSSQL and
    > > >substituting null's with "" there. This means a lot of
    > > typing for me, which
    > > >is never a good thing.
    > > >
    > > >Does anyone have a better solution to my problem?
    > > >
    > > >
    > > >.
    > > >
    >
    >

    Guest
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  4. Aemca #4

    Default Re: Question: Best way to handle DBNULL in datareaders

    any suggestions on how to implement this ?
    aka what should be in there

    and this is the way that it is implemented, the .getvalue / getstring are
    omitted.


    <DanR@REMOVETHISTOGETTOME-warshawgroup.com> wrote in message
    news:#pz2GmGTDHA.2148@TK2MSFTNGP10.phx.gbl...
    > You could make a function which wraps the null and put that in...
    >
    > Textbox1.text = CleanThis(myreader(1))
    >
    > Have you tried adding the null to an empty string?
    >
    > Textbox1.text = "" & myreader(1)
    >
    > or something like that
    >
    > It's not clear if you are using getstring or getvalue or what
    >
    > ...?
    >
    > "Aemca" <none@none.com> wrote in message
    > news:eCQJpFGTDHA.2852@tk2msftngp13.phx.gbl...
    > > That was my first solution but thats way 2 much work to type that for
    each
    > > value i want to use.
    > >
    > > So this is not really a better solution for me.
    > >
    > >
    > > > Hi
    > > >
    > > > Alternative is check before assigning as TextBox value.
    > > >
    > > > TextBox1.Text =myRow["ColumnName"]==DBNull.Value)?"":
    > > > (string)myRow["ColumnName"]
    > > >
    > > > HTH
    > > > Ravikanth
    > > >
    > > >
    > > > >-----Original Message-----
    > > > >Im looking for the best way to handle DBNULL's in
    > > > datareaders.
    > > > >
    > > > >In a project im currently working on im using a lot of
    > > > optional data with
    > > > >datareaders.
    > > > >
    > > > >Using the following syntax im getting errors when the
    > > > field contains a
    > > > >DBNULL value
    > > > >Textbox1.text = myreader(1)
    > > > >
    > > > >My current solution for this is using the isnull
    > > > function of MSSQL and
    > > > >substituting null's with "" there. This means a lot of
    > > > typing for me, which
    > > > >is never a good thing.
    > > > >
    > > > >Does anyone have a better solution to my problem?
    > > > >
    > > > >
    > > > >.
    > > > >
    > >
    > >
    >
    >

    Aemca Guest
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  5. PJ #5

    Default Re: Question: Best way to handle DBNULL in datareaders

    You can simply use .ToString() on varchar fields.

    dr(0).ToString()

    That will return an empty string if it's a null varchar field.

    "Aemca" <none@none.com> wrote in message
    news:urhX2zGTDHA.2084@TK2MSFTNGP11.phx.gbl...
    > any suggestions on how to implement this ?
    > aka what should be in there
    >
    > and this is the way that it is implemented, the .getvalue / getstring are
    > omitted.
    >
    >
    > <DanR@REMOVETHISTOGETTOME-warshawgroup.com> wrote in message
    > news:#pz2GmGTDHA.2148@TK2MSFTNGP10.phx.gbl...
    > > You could make a function which wraps the null and put that in...
    > >
    > > Textbox1.text = CleanThis(myreader(1))
    > >
    > > Have you tried adding the null to an empty string?
    > >
    > > Textbox1.text = "" & myreader(1)
    > >
    > > or something like that
    > >
    > > It's not clear if you are using getstring or getvalue or what
    > >
    > > ...?
    > >
    > > "Aemca" <none@none.com> wrote in message
    > > news:eCQJpFGTDHA.2852@tk2msftngp13.phx.gbl...
    > > > That was my first solution but thats way 2 much work to type that for
    > each
    > > > value i want to use.
    > > >
    > > > So this is not really a better solution for me.
    > > >
    > > >
    > > > > Hi
    > > > >
    > > > > Alternative is check before assigning as TextBox value.
    > > > >
    > > > > TextBox1.Text =myRow["ColumnName"]==DBNull.Value)?"":
    > > > > (string)myRow["ColumnName"]
    > > > >
    > > > > HTH
    > > > > Ravikanth
    > > > >
    > > > >
    > > > > >-----Original Message-----
    > > > > >Im looking for the best way to handle DBNULL's in
    > > > > datareaders.
    > > > > >
    > > > > >In a project im currently working on im using a lot of
    > > > > optional data with
    > > > > >datareaders.
    > > > > >
    > > > > >Using the following syntax im getting errors when the
    > > > > field contains a
    > > > > >DBNULL value
    > > > > >Textbox1.text = myreader(1)
    > > > > >
    > > > > >My current solution for this is using the isnull
    > > > > function of MSSQL and
    > > > > >substituting null's with "" there. This means a lot of
    > > > > typing for me, which
    > > > > >is never a good thing.
    > > > > >
    > > > > >Does anyone have a better solution to my problem?
    > > > > >
    > > > > >
    > > > > >.
    > > > > >
    > > >
    > > >
    > >
    > >
    >
    >

    PJ Guest
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  6. Aemca #6

    Default Re: Question: Best way to handle DBNULL in datareaders


    "PJ" <pjwal@hotmail.com> wrote in message
    news:ODfDfQITDHA.2180@TK2MSFTNGP10.phx.gbl...
    > You can simply use .ToString() on varchar fields.
    >
    > dr(0).ToString()
    >
    > That will return an empty string if it's a null varchar field.
    >
    > "Aemca" <none@none.com> wrote in message
    > news:urhX2zGTDHA.2084@TK2MSFTNGP11.phx.gbl...
    > > any suggestions on how to implement this ?
    > > aka what should be in there
    > >
    > > and this is the way that it is implemented, the .getvalue / getstring
    are
    > > omitted.
    > >
    > >
    > > <DanR@REMOVETHISTOGETTOME-warshawgroup.com> wrote in message
    > > news:#pz2GmGTDHA.2148@TK2MSFTNGP10.phx.gbl...
    > > > You could make a function which wraps the null and put that in...
    > > >
    > > > Textbox1.text = CleanThis(myreader(1))
    > > >
    > > > Have you tried adding the null to an empty string?
    > > >
    > > > Textbox1.text = "" & myreader(1)
    > > >
    > > > or something like that
    > > >
    > > > It's not clear if you are using getstring or getvalue or what
    > > >
    > > > ...?
    > > >
    > > > "Aemca" <none@none.com> wrote in message
    > > > news:eCQJpFGTDHA.2852@tk2msftngp13.phx.gbl...
    > > > > That was my first solution but thats way 2 much work to type that
    for
    > > each
    > > > > value i want to use.
    > > > >
    > > > > So this is not really a better solution for me.
    > > > >
    > > > >
    > > > > > Hi
    > > > > >
    > > > > > Alternative is check before assigning as TextBox value.
    > > > > >
    > > > > > TextBox1.Text =myRow["ColumnName"]==DBNull.Value)?"":
    > > > > > (string)myRow["ColumnName"]
    > > > > >
    > > > > > HTH
    > > > > > Ravikanth
    > > > > >
    > > > > >
    > > > > > >-----Original Message-----
    > > > > > >Im looking for the best way to handle DBNULL's in
    > > > > > datareaders.
    > > > > > >
    > > > > > >In a project im currently working on im using a lot of
    > > > > > optional data with
    > > > > > >datareaders.
    > > > > > >
    > > > > > >Using the following syntax im getting errors when the
    > > > > > field contains a
    > > > > > >DBNULL value
    > > > > > >Textbox1.text = myreader(1)
    > > > > > >
    > > > > > >My current solution for this is using the isnull
    > > > > > function of MSSQL and
    > > > > > >substituting null's with "" there. This means a lot of
    > > > > > typing for me, which
    > > > > > >is never a good thing.
    > > > > > >
    > > > > > >Does anyone have a better solution to my problem?
    > > > > > >
    > > > > > >
    > > > > > >.
    > > > > > >
    > > > >
    > > > >
    > > >
    > > >
    > >
    > >
    >
    >

    Aemca Guest
    Reply With Quote Reply With Quote
  7. Aemca #7

    Default Re: Question: Best way to handle DBNULL in datareaders

    thx :)

    "PJ" <pjwal@hotmail.com> wrote in message
    news:ODfDfQITDHA.2180@TK2MSFTNGP10.phx.gbl...
    > You can simply use .ToString() on varchar fields.
    >
    > dr(0).ToString()
    >
    > That will return an empty string if it's a null varchar field.
    >
    > "Aemca" <none@none.com> wrote in message
    > news:urhX2zGTDHA.2084@TK2MSFTNGP11.phx.gbl...
    > > any suggestions on how to implement this ?
    > > aka what should be in there
    > >
    > > and this is the way that it is implemented, the .getvalue / getstring
    are
    > > omitted.
    > >
    > >
    > > <DanR@REMOVETHISTOGETTOME-warshawgroup.com> wrote in message
    > > news:#pz2GmGTDHA.2148@TK2MSFTNGP10.phx.gbl...
    > > > You could make a function which wraps the null and put that in...
    > > >
    > > > Textbox1.text = CleanThis(myreader(1))
    > > >
    > > > Have you tried adding the null to an empty string?
    > > >
    > > > Textbox1.text = "" & myreader(1)
    > > >
    > > > or something like that
    > > >
    > > > It's not clear if you are using getstring or getvalue or what
    > > >
    > > > ...?
    > > >
    > > > "Aemca" <none@none.com> wrote in message
    > > > news:eCQJpFGTDHA.2852@tk2msftngp13.phx.gbl...
    > > > > That was my first solution but thats way 2 much work to type that
    for
    > > each
    > > > > value i want to use.
    > > > >
    > > > > So this is not really a better solution for me.
    > > > >
    > > > >
    > > > > > Hi
    > > > > >
    > > > > > Alternative is check before assigning as TextBox value.
    > > > > >
    > > > > > TextBox1.Text =myRow["ColumnName"]==DBNull.Value)?"":
    > > > > > (string)myRow["ColumnName"]
    > > > > >
    > > > > > HTH
    > > > > > Ravikanth
    > > > > >
    > > > > >
    > > > > > >-----Original Message-----
    > > > > > >Im looking for the best way to handle DBNULL's in
    > > > > > datareaders.
    > > > > > >
    > > > > > >In a project im currently working on im using a lot of
    > > > > > optional data with
    > > > > > >datareaders.
    > > > > > >
    > > > > > >Using the following syntax im getting errors when the
    > > > > > field contains a
    > > > > > >DBNULL value
    > > > > > >Textbox1.text = myreader(1)
    > > > > > >
    > > > > > >My current solution for this is using the isnull
    > > > > > function of MSSQL and
    > > > > > >substituting null's with "" there. This means a lot of
    > > > > > typing for me, which
    > > > > > >is never a good thing.
    > > > > > >
    > > > > > >Does anyone have a better solution to my problem?
    > > > > > >
    > > > > > >
    > > > > > >.
    > > > > > >
    > > > >
    > > > >
    > > >
    > > >
    > >
    > >
    >
    >

    Aemca Guest
    Reply With Quote Reply With Quote
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