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Simple .NET/ASP.NET PDF document editor web control SDKIn this section, we will present some additional recommendations for applying the .NET Library Design Guidelines to F# programming. We do this by making a series of recommendations that can be read as extensions to these guidelines. Recommendation: Use the .NET naming and capitalization conventions where possible. Table 19-2 summarizes the .NET guidelines for naming and capitalization in code. We have added our own recommendations for how these should be adjusted for some F# constructs. This table refers to the following categories of names: PascalCase: LeftButton and TopRight, for example camelCase: leftButton and topRight, for example Verb: A verb or verb phrase; performAction or SetValue, for example Noun: A noun or noun phrase; cost or ValueAfterDepreciation, for example Adjective: An adjective or adjectival phrase; Comparable or Disposable, for example In general, the .NET guidelines strongly discourage the use of abbreviations (for example, use OnButtonClick rather than OnBtnClick ). Common abbreviations such as Async for Asynchronous are tolerated. This guideline has historically been broken by functional programming; for example, List.iter uses an abbreviation for iterate. For this reason, using abbreviations tends to be tolerated to a greater degree in F# programming, though we discourage using additional abbreviations beyond those already found in existing F# libraries. barcode generator excel mac, barcode font for excel 2010 free, barcode generator macro excel, using barcode in excel 2007, any size barcode generator in excel free to download, excel 2007 barcode generator free, barcode addin for excel 2007, barcode add in excel freeware, free barcode font excel 2010, barcode add in for excel 2010,Performance and scalability are affected adversely if an application has to authenticate using the end user s database password. Consider an application that uses a connection pool of a maximum 100 connections for a system serving 5,000 end users. Every time a new user logs in, the likelihood of the user s connection not existing in the pool is high, simply because each user connects to a different account. This means that, more likely than not, an existing connection in the pool has to be closed and replaced with a newly created connection. This defeats the purpose of connection pooling to a large extent, especially when you use an implicit connection cache, where each session requires the creation of a physical connection. Some of the problems just mentioned would be mitigated if all application end users shared a smaller set of database user accounts based on their roles (i.e., an N-to-M mapping). However, this gives rise to new set of problems. One problem is that different application users have to share the same password for the shared database account, leading to poor security. Another problem, as mentioned earlier, is that the user actions cannot be audited effectively. What we really need is for the application to log into the database using a common database account on behalf of an end user without requiring it to present the end user s database password. In other words, the account midtier proxies for the end user. This is where proxy authentication (also known as n-tier authentication) comes in. Acronyms such as XML are not abbreviations and are widely used in .NET libraries, though in uncapitalized form (Xml). Only well-known, widely recognized acronyms should be used. The .NET guidelines say that casing cannot be used to avoid name collisions and that you must assume that some client languages are case insensitive. For example, Visual Basic is case insensitive. valuesB[1][2] = "2"; valuesB[1][3] = "3"; valuesB[1][3] = "4"; //etc... The two initial arrays are both arrays of arrays. There will be an array containing a list of display items and an array of values for each item in the first list. You ll get going with the initial first few lines of code, which are static. Remember that you need to wrap your array declarations in their own script block. StringBuilder sb = new StringBuilder(); sb.Append("<SCRIPT LANGUAGE='JavaScript'>\n"); sb.Append("listsB = new Array;\n"); sb.Append("valuesB = new Array;\n"); Then, for each row in the table the first list is bound to, you ll add an array of display items and an array of item values. You ll use a DataView to find all of the pool halls in that city. int i = 0; foreach (DataRow dr in ds.Tables[1].Rows) { sb.Append( string.Format( "listsB[{0}] = new Array;\n",i)); sb.Append( string.Format( "valuesB[{0}] = new Array;\n", i)); DataView dv = new DataView( ds.Tables[2], string.Format("City = '{0}'", dr[0]), "", DataViewRowState.CurrentRows); Then, for each matching pool hall, you ll generate an entry in each of the two nested arrays: int j = 0; foreach (DataRowView drv in dv) { sb.Append( string.Format( "listsB[{0}][{1}] = \"{2}\";", i, j, drv["Name"])); sb.Append( string.Format( "valuesB[{0}][{1}] = \"{2}\";", i, j, drv["id"])); Proxy Authentication (N-Tier Authentication)
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