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How do I use IValidatableObject?

...upedByMembers) { ModelState.AddModelError( member.Key, string.Join(". ", member.Select(m => m.Error))); } share | improve this answer | follow ...
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How to output only captured groups with sed?

... what you don't want to be output as well as specifying what you do want. string='This is a sample 123 text and some 987 numbers' echo "$string" | sed -rn 's/[^[:digit:]]*([[:digit:]]+)[^[:digit:]]+([[:digit:]]+)[^[:digit:]]*/\1 \2/p' This says: don't default to printing each line (-n) exclude ...
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How do I check if a given Python string is a substring of another one? [duplicate]

I have two strings and I would like to check whether the first is a substring of the other. Does Python have such a built-in functionality? ...
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Drop columns whose name contains a specific string from pandas DataFrame

...er, and Idiomatic: str.contains In recent versions of pandas, you can use string methods on the index and columns. Here, str.startswith seems like a good fit. To remove all columns starting with a given substring: df.columns.str.startswith('Test') # array([ True, False, False, False]) df.loc[:,~...
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Check if EditText is empty. [closed]

... findViewById(R.id.editUsername); sUsername = usernameEditText.getText().toString(); if (sUsername.matches("")) { Toast.makeText(this, "You did not enter a username", Toast.LENGTH_SHORT).show(); return; } share ...
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Is it expensive to use try-catch blocks even if an exception is never thrown?

... Let's measure it, shall we? public abstract class Benchmark { final String name; public Benchmark(String name) { this.name = name; } abstract int run(int iterations) throws Throwable; private BigDecimal time() { try { int nextI = 1; i...
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Deciding between HttpClient and WebClient

... result = responseTask.Result; var readTask = result.Content.ReadAsStringAsync().Result; } private void CallGetHttpClient() { var httpClient = new HttpClient(); httpClient.BaseAddress = new Uri("https://localhost:44354/api/test/"); var responseTask = http...
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Using Ajax.BeginForm with ASP.NET MVC 3 Razor

... Example: Model: public class MyViewModel { [Required] public string Foo { get; set; } } Controller: public class HomeController : Controller { public ActionResult Index() { return View(new MyViewModel()); } [HttpPost] public ActionResult Index(MyViewMode...
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Rails migration for change column

...ata. I've run into several situations where the existing data, let's say a String can be implicitly converted into the new datatype, let's say Date. In this situation, it's helpful to know you can create migrations with data conversions. Personally, I like putting these in my model file, and then ...
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How do you append to an already existing string?

I want append to a string so that every time I loop over it will add say "test" to the string. 7 Answers ...